# 5. defaultSettings.yaml¶

latexindent.pl loads its settings from defaultSettings.yaml. The idea is to separate the behaviour of the script from the internal working – this is very similar to the way that we separate content from form when writing our documents in LaTeX.

If you look in defaultSettings.yaml you’ll find the switches that govern the behaviour of latexindent.pl. If you’re not sure where defaultSettings.yaml resides on your computer, don’t worry as indent.log will tell you where to find it. defaultSettings.yaml is commented, but here is a description of what each switch is designed to do. The default value is given in each case; whenever you see integer in this section, assume that it must be greater than or equal to 0 unless otherwise stated.

For most of the settings in defaultSettings.yaml that are specified as integers, then we understand 0 to represent ‘off’ and 1 to represent ‘on’. For fields that allow values other than 0 or 1, it is hoped that the specific context and associated commentary should make it clear which values are allowed.

fileExtensionPreference:fields

latexindent.pl can be called to act on a file without specifying the file extension. For example we can call

latexindent.pl myfile


in which case the script will look for myfile with the extensions specified in fileExtensionPreference in their numeric order. If no match is found, the script will exit. As with all of the fields, you should change and/or add to this as necessary.

Listing 32 fileExtensionPreference
 44 45 46 47 48 fileExtensionPreference: .tex: 1 .sty: 2 .cls: 3 .bib: 4 

Calling latexindent.pl myfile with the (default) settings specified in Listing 32 means that the script will first look for myfile.tex, then myfile.sty, myfile.cls, and finally myfile.bib in order [1].

## 5.1. Backup and log file preferences¶

backupExtension:extension name

If you call latexindent.pl with the -w switch (to overwrite myfile.tex) then it will create a backup file before doing any indentation; the default extension is .bak, so, for example, myfile.bak0 would be created when calling latexindent.pl myfile.tex for the first time.

By default, every time you subsequently call latexindent.pl with the -w to act upon myfile.tex, it will create successive back up files: myfile.bak1, myfile.bak2, etc.

onlyOneBackUp:integer

If you don’t want a backup for every time that you call latexindent.pl (so you don’t want myfile.bak1, myfile.bak2, etc) and you simply want myfile.bak (or whatever you chose backupExtension to be) then change onlyOneBackUp to 1; the default value of onlyOneBackUp is 0.

maxNumberOfBackUps:integer

Some users may only want a finite number of backup files, say at most $$3$$, in which case, they can change this switch. The smallest value of maxNumberOfBackUps is $$0$$ which will not prevent backup files being made; in this case, the behaviour will be dictated entirely by onlyOneBackUp. The default value of maxNumberOfBackUps is 0.

cycleThroughBackUps:integer

Some users may wish to cycle through backup files, by deleting the oldest backup file and keeping only the most recent; for example, with maxNumberOfBackUps: 4, and cycleThroughBackUps set to 1 then the copy procedure given below would be obeyed.

copy myfile.bak1 to myfile.bak0
copy myfile.bak2 to myfile.bak1
copy myfile.bak3 to myfile.bak2
copy myfile.bak4 to myfile.bak3


The default value of cycleThroughBackUps is 0.

logFilePreferences:fields

latexindent.pl writes information to indent.log, some of which can be customized by changing logFilePreferences; see Listing 33. If you load your own user settings (see Section 4) then latexindent.pl will detail them in indent.log; you can choose not to have the details logged by switching showEveryYamlRead to 0. Once all of your settings have been loaded, you can see the amalgamated settings in the log file by switching showAmalgamatedSettings to 1, if you wish.

Listing 33 logFilePreferences
  88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 logFilePreferences: showEveryYamlRead: 1 showAmalgamatedSettings: 0 showDecorationStartCodeBlockTrace: 0 showDecorationFinishCodeBlockTrace: 0 endLogFileWith: '--------------' showGitHubInfoFooter: 1 Dumper: Terse: 1 Indent: 1 Useqq: 1 Deparse: 1 Quotekeys: 0 Sortkeys: 1 Pair: " => " 

When either of the trace modes (see page page:traceswitch) are active, you will receive detailed information in indent.log. You can specify character strings to appear before and after the notification of a found code block using, respectively, showDecorationStartCodeBlockTrace and showDecorationFinishCodeBlockTrace. A demonstration is given in Section 12.8.

The log file will end with the characters given in endLogFileWith, and will report the GitHub address of latexindent.pl to the log file if showGitHubInfoFooter is set to 1.

Note: latexindent.pl no longer uses the log4perl module to handle the creation of the logfile.

Some of the options for Perl’s Dumper module can be specified in Listing 33; see (“Data::Dumper Module” n.d.) and (“Data Dumper Demonstration” n.d.) for more information. These options will mostly be helpful for those calling latexindent.pl with the -tt option described in Section 3.2.

## 5.2. Verbatim code blocks¶

verbatimEnvironments:fields

A field that contains a list of environments that you would like left completely alone – no indentation will be performed on environments that you have specified in this field, see Listing 34.

Listing 34 verbatimEnvironments
 106 107 108 109 verbatimEnvironments: verbatim: 1 lstlisting: 1 minted: 1 
Listing 35 verbatimCommands
 112 113 114 verbatimCommands: verb: 1 lstinline: 1 

Note that if you put an environment in verbatimEnvironments and in other fields such as lookForAlignDelims or noAdditionalIndent then latexindent.pl will always prioritize verbatimEnvironments.

You can, optionally, specify the verbatim field using the name field which takes a regular expression as its argument; thank you to (XuehaiPan 2021) for contributing this feature.

For demonstration, then assuming that your file contains the environments latexcode, latexcode*, pythoncode and pythoncode*, then the listings given in Listing 36 and Listing 37 are equivalent.

Listing 36 nameAsRegex1.yaml
verbatimEnvironments:
latexcode: 1
latexcode*: 1
pythoncode: 1
pythoncode*: 1

Listing 37 nameAsRegex2.yaml
verbatimEnvironments:
nameAsRegex:
name: '\w+code\*?'
lookForThis: 1


With reference to Listing 37:

• the name field as specified here means any word followed by the word code, optionally followed by *;
• we have used nameAsRegex to identify this field, but you can use any description you like;
• the lookForThis field is optional, and can take the values 0 (off) or 1 (on); by default, it is assumed to be 1 (on).
verbatimCommands:fields

A field that contains a list of commands that are verbatim commands, for example \verb; any commands populated in this field are protected from line breaking routines (only relevant if the -m is active, see Section 6).

With reference to Listing 35, by default latexindent.pl looks for \verb immediately followed by another character, and then it takes the body as anything up to the next occurrence of the character; this means that, for example, \verb!x+3! is treated as a verbatimCommands.

You can, optionally, specify the verbatimCommands field using the name field which takes a regular expression as its argument; thank you to (XuehaiPan 2021) for contributing this feature.

For demonstration, then assuming that your file contains the commands verbinline, myinline then the listings given in Listing 38 and Listing 39 are equivalent.

Listing 38 nameAsRegex3.yaml
verbatimCommands:
verbinline: 1
myinline: 1

Listing 39 nameAsRegex4.yaml
verbatimCommands:
nameAsRegex:
name: '\w+inline'
lookForThis: 1


With reference to Listing 39:

• the name field as specified here means any word followed by the word inline;
• we have used nameAsRegex to identify this field, but you can use any description you like;
• the lookForThis field is optional, and can take the values 0 (off) or 1 (on); by default, it is assumed to be 1 (on).
noIndentBlock:fields

If you have a block of code that you don’t want latexindent.pl to touch (even if

it is not a verbatim-like environment) then you can wrap it in an environment from noIndentBlock; you can use any name you like for this, provided you populate it as demonstrate in Listing 40.

Listing 40 noIndentBlock
 119 120 121 noIndentBlock: noindent: 1 cmhtest: 1 

Of course, you don’t want to have to specify these as null environments in your code, so you use them with a comment symbol, %, followed by as many spaces (possibly none) as you like; see Listing 41 for example.

Listing 41 noIndentBlock.tex
% \begin{noindent}
some before text
this code
won't
be touched
by
latexindent.pl!
some after text
% \end{noindent}


Important note: it is assumed that the noindent block statements specified in this way appear on their own line.

The noIndentBlock fields can also be specified in terms of begin and end fields. We use the code in Listing 42 to demonstrate this feature.

Listing 42 noIndentBlock1.tex
some before text
this code
won't
be touched
by
latexindent.pl!
some after text


The settings given in Listing 43 and Listing 44 are equivalent:

Listing 43 noindent1.yaml
noIndentBlock:
demo:
begin: 'some\hbefore'
body: '.*?'
end: 'some\hafter\htext'
lookForThis: 1

Listing 44 noindent2.yaml
noIndentBlock:
demo:
begin: 'some\hbefore'
end: 'some\hafter\htext'

Listing 45 noindent3.yaml
noIndentBlock:
demo:
begin: 'some\hbefore'
body: '.*?'
end: 'some\hafter\htext'
lookForThis: 0


Upon running the commands

latexindent.pl -l noindent1.yaml noindent1
latexindent.pl -l noindent2.yaml noindent1


then we receive the output given in Listing 46.

Listing 46 noIndentBlock1.tex using Listing 43 or Listing 44
some before text
this code
won't
be touched
by
latexindent.pl!
some after text


The begin, body and end fields for noIndentBlock are all regular expressions. If the body field is not specified, then it takes a default value of .*? which is written explicitly in Listing 43. In this context, we interpret .*? in words as the fewest number of characters (possibly none) until the ‘end’ field is reached.

The lookForThis field is optional, and can take the values 0 (off) or 1 (on); by default, it is assumed to be 1 (on).

Using Listing 45 demonstrates setting lookForThis to 0 (off); running the command

latexindent.pl -l noindent3.yaml noindent1


gives the output in Listing 47.

Listing 47 noIndentBlock1.tex using Listing 45
some before text
this code
won't
be touched
by
latexindent.pl!
some after text


We will demonstrate this feature later in the documentation in Listing 538.

You can, optionally, specify the noIndentBlock field using the name field which takes a regular expression as its argument; thank you to (XuehaiPan 2021) for contributing this feature.

For demonstration, then assuming that your file contains the environments testnoindent, testnoindent* then the listings given in Listing 48 and Listing 49 are equivalent.

Listing 48 nameAsRegex5.yaml
noIndentBlock:
mytest:
begin: '\\begin\{testnoindent\*?\}'
end: '\\end\{testnoindent\*?\}'

Listing 49 nameAsRegex6.yaml
noIndentBlock:
nameAsRegex:
name: '\w+noindent\*?'
lookForThis: 1


With reference to Listing 49:

• the name field as specified here means any word followed by the word noindent, optionally followed by *;
• we have used nameAsRegex to identify this field, but you can use any description you like;
• the lookForThis field is optional, and can take the values 0 (off) or 1 (on); by default, it is assumed to be 1 (on).

## 5.3. filecontents and preamble¶

fileContentsEnvironments:field

Before latexindent.pl determines the difference between preamble (if any) and the main document, it first searches for any of the environments specified in fileContentsEnvironments, see Listing 50. The behaviour of latexindent.pl on these environments is determined by their location (preamble or not), and the value indentPreamble, discussed next.

Listing 50 fileContentsEnvironments
 125 126 127 fileContentsEnvironments: filecontents: 1 filecontents*: 1 
indentPreamble:0|1

The preamble of a document can sometimes contain some trickier code for latexindent.pl to operate upon. By default, latexindent.pl won’t try to operate on the preamble (as indentPreamble is set to 0, by default), but if you’d like latexindent.pl to try then change indentPreamble to 1.

lookForPreamble:fields

Not all files contain preamble; for example, sty, cls and bib files typically do not. Referencing Listing 51, if you set, for example, .tex to 0, then regardless of the setting of the value of indentPreamble, preamble will not be assumed when operating upon .tex files.

Listing 51 lookForPreamble
 133 134 135 136 137 lookForPreamble: .tex: 1 .sty: 0 .cls: 0 .bib: 0 
preambleCommandsBeforeEnvironments:0|1

Assuming that latexindent.pl is asked to operate upon the preamble of a document, when this switch is set to 0 then environment code blocks will be sought first, and then command code blocks. When this switch is set to 1, commands will be sought first. The example that first motivated this switch contained the code given in Listing 52.

Listing 52 Motivating preambleCommandsBeforeEnvironments
...
postfoothook=\end{mdframed},
...


## 5.4. Indentation and horizontal space¶

defaultIndent:horizontal space

This is the default indentation used in the absence of other details for the code block with which we are working. The default value is \t which means a tab; we will explore customisation beyond defaultIndent in Section 5.8.

If you’re interested in experimenting with latexindent.pl then you can remove all indentation by setting defaultIndent: "".

removeTrailingWhitespace:fields

Trailing white space can be removed both before and after processing the document, as detailed in Listing 53; each of the fields can take the values 0 or 1. See Listing 429 and Listing 430 and Listing 431 for before and after results. Thanks to (Voßkuhle 2013) for providing this feature.

Listing 53 removeTrailingWhitespace
 150 151 152 removeTrailingWhitespace: beforeProcessing: 0 afterProcessing: 1 
Listing 54 removeTrailingWhitespace (alt)
removeTrailingWhitespace: 1


You can specify removeTrailingWhitespace simply as 0 or 1, if you wish; in this case, latexindent.pl will set both beforeProcessing and afterProcessing to the value you specify; see Listing 54.

## 5.5. Aligning at delimiters¶

lookForAlignDelims:fields

This contains a list of code blocks that are operated upon in a special way by latexindent.pl (see Listing 55). In fact, the fields in lookForAlignDelims can actually take two different forms: the basic version is shown in Listing 55 and the advanced version in Listing 58; we will discuss each in turn.

Listing 55 lookForAlignDelims (basic)
lookForAlignDelims:
tabular: 1
tabularx: 1
longtable: 1
array: 1
matrix: 1
...


Specifying code blocks in this field instructs latexindent.pl to try and align each column by its alignment delimiters. It does have some limitations (discussed further in Section 10), but in many cases it will produce results such as those in Listing 56 and Listing 57.

If you find that latexindent.pl does not perform satisfactorily on such environments then you can set the relevant key to 0, for example tabular: 0; alternatively, if you just want to ignore specific instances of the environment, you could wrap them in something from noIndentBlock (see Listing 40).

Listing 56 tabular1.tex
\begin{tabular}{cccc}
1&	2 &3       &4\\
5& &6       &\\
\end{tabular}

Listing 57 tabular1.tex default output
\begin{tabular}{cccc}
1 & 2 & 3 & 4 \\
5 &   & 6 &   \\
\end{tabular}


If, for example, you wish to remove the alignment of the \\ within a delimiter-aligned block, then the advanced form of lookForAlignDelims shown in Listing 58 is for you.

Listing 58 lookForAlignDelims (advanced)
 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 lookForAlignDelims: tabular: delims: 1 alignDoubleBackSlash: 1 spacesBeforeDoubleBackSlash: 1 multiColumnGrouping: 0 alignRowsWithoutMaxDelims: 1 spacesBeforeAmpersand: 1 spacesAfterAmpersand: 1 justification: left alignFinalDoubleBackSlash: 0 dontMeasure: 0 delimiterRegEx: '(?

Note that you can use a mixture of the basic and advanced form: in Listing 58 tabular and tabularx are advanced and longtable is basic. When using the advanced form, each field should receive at least 1 sub-field, and can (but does not have to) receive any of the following fields:

• delims: binary switch (0 or 1) equivalent to simply specifying, for example, tabular: 1 in the basic version shown in Listing 55. If delims is set to 0 then the align at ampersand routine will not be called for this code block (default: 1);
• alignDoubleBackSlash: binary switch (0 or 1) to determine if \\ should be aligned (default: 1);
• spacesBeforeDoubleBackSlash: optionally, specifies the number (integer $$\geq$$ 0) of spaces to be inserted before \\ (default: 1);
• multiColumnGrouping: binary switch (0 or 1) that details if latexindent.pl should group columns above and below a \multicolumn command (default: 0);
• alignRowsWithoutMaxDelims: binary switch (0 or 1) that details if rows that do not contain the maximum number of delimeters should be formatted so as to have the ampersands aligned (default: 1);
• spacesBeforeAmpersand: optionally specifies the number (integer $$\geq$$ 0) of spaces to be placed before ampersands (default: 1);
• spacesAfterAmpersand: optionally specifies the number (integer $$\geq$$ 0) of spaces to be placed After ampersands (default: 1);
• justification: optionally specifies the justification of each cell as either left or right (default: left);
• alignFinalDoubleBackSlash optionally specifies if the final double back slash should be used for alignment (default: 0);
• dontMeasure optionally specifies if user-specified cells, rows or the largest entries should not be measured (default: 0);
• delimiterRegEx optionally specifies the pattern matching to be used for the alignment delimeter (default: (?<!\\)(&)*);
• delimiterJustification optionally specifies the justification for the alignment delimeters (default: left); note that this feature is only useful if you have delimiters of different lengths in the same column, discussed in Section 5.5.4;
• lookForChildCodeBlocks optionally instructs latexindent.pl to search for child code blocks or not (default: 1), discussed in Section 5.5.5.

We will explore most of these features using the file tabular2.tex in Listing 59 (which contains a \multicolumn command), and the YAML files in Listing 60Listing 66; we will explore alignFinalDoubleBackSlash in Listing 87; the dontMeasure feature will be described in Section 5.5.3, and delimiterRegEx in Section 5.5.4.

Listing 59 tabular2.tex
\begin{tabular}{cccc}
A&    B & C       &D\\
AAA&    BBB & CCC       &DDD\\
one&    two & three       &four\\
five& &six      &\\
seven & \\
\end{tabular}

Listing 60 tabular2.yaml
lookForAlignDelims:
tabular:
multiColumnGrouping: 1

Listing 61 tabular3.yaml
lookForAlignDelims:
tabular:
alignRowsWithoutMaxDelims: 0

Listing 62 tabular4.yaml
lookForAlignDelims:
tabular:
spacesBeforeAmpersand: 4

Listing 63 tabular5.yaml
lookForAlignDelims:
tabular:
spacesAfterAmpersand: 4

Listing 64 tabular6.yaml
lookForAlignDelims:
tabular:
alignDoubleBackSlash: 0

Listing 65 tabular7.yaml
lookForAlignDelims:
tabular:
spacesBeforeDoubleBackSlash: 0

Listing 66 tabular8.yaml
lookForAlignDelims:
tabular:
justification: "right"


On running the commands

latexindent.pl tabular2.tex
latexindent.pl tabular2.tex -l tabular2.yaml
latexindent.pl tabular2.tex -l tabular3.yaml
latexindent.pl tabular2.tex -l tabular2.yaml,tabular4.yaml
latexindent.pl tabular2.tex -l tabular2.yaml,tabular5.yaml
latexindent.pl tabular2.tex -l tabular2.yaml,tabular6.yaml
latexindent.pl tabular2.tex -l tabular2.yaml,tabular7.yaml
latexindent.pl tabular2.tex -l tabular2.yaml,tabular8.yaml


we obtain the respective outputs given in Listing 67Listing 74.

Listing 67 tabular2.tex default output
\begin{tabular}{cccc}
A                                 & B                                  & C     & D    \\
AAA                               & BBB                                & CCC   & DDD  \\
one                               & two                                & three & four \\
five                              &                                    & six   &      \\
seven                             &                                                   \\
\end{tabular}

Listing 68 tabular2.tex using Listing 60
\begin{tabular}{cccc}
A     & B                         & C     & D                          \\
AAA   & BBB                       & CCC   & DDD                        \\
one   & two                       & three & four                       \\
five  &                           & six   &                            \\
seven &                                                                \\
\end{tabular}

Listing 69 tabular2.tex using Listing 61
\begin{tabular}{cccc}
A    & B   & C     & D                                                 \\
AAA  & BBB & CCC   & DDD                                               \\
one  & two & three & four                                              \\
five &     & six   &                                                   \\
seven &                                                                \\
\end{tabular}

Listing 70 tabular2.tex using Listing 60 and Listing 62
\begin{tabular}{cccc}
A        & B                         & C        & D                       \\
AAA      & BBB                       & CCC      & DDD                     \\
one      & two                       & three    & four                    \\
five     &                           & six      &                         \\
seven    &                                                                \\
\end{tabular}

Listing 71 tabular2.tex using Listing 60 and Listing 63
\begin{tabular}{cccc}
A     &    B                      &    C     &    D                       \\
AAA   &    BBB                    &    CCC   &    DDD                     \\
one   &    two                    &    three &    four                    \\
five  &                           &    six   &                            \\
seven &                                                                   \\
\end{tabular}

Listing 72 tabular2.tex using Listing 60 and Listing 64
\begin{tabular}{cccc}
A     & B                         & C     & D \\
AAA   & BBB                       & CCC   & DDD \\
one   & two                       & three & four \\
five  &                           & six   & \\
seven & \\
\end{tabular}

Listing 73 tabular2.tex using Listing 60 and Listing 65
\begin{tabular}{cccc}
A     & B                         & C     & D                         \\
AAA   & BBB                       & CCC   & DDD                       \\
one   & two                       & three & four                      \\
five  &                           & six   &                           \\
seven &                                                               \\
\end{tabular}

Listing 74 tabular2.tex using Listing 60 and Listing 66
\begin{tabular}{cccc}
A &   B &                           C &    D \\
AAA & BBB &                         CCC &  DDD \\
one & two &                       three & four \\
five &     &                         six &      \\
seven &                                          \\
\end{tabular}


Notice in particular:

• in both Listing 67 and Listing 68 all rows have been aligned at the ampersand, even those that do not contain the maximum number of ampersands (3 ampersands, in this case);
• in Listing 67 the columns have been aligned at the ampersand;
• in Listing 68 the \multicolumn command has grouped the $$2$$ columns beneath and above it, because multiColumnGrouping is set to $$1$$ in Listing 60;
• in Listing 69 rows 3 and 6 have not been aligned at the ampersand, because alignRowsWithoutMaxDelims has been to set to $$0$$ in Listing 61; however, the \\ have still been aligned;
• in Listing 70 the columns beneath and above the \multicolumn commands have been grouped (because multiColumnGrouping is set to $$1$$), and there are at least $$4$$ spaces before each aligned ampersand because spacesBeforeAmpersand is set to $$4$$;
• in Listing 71 the columns beneath and above the \multicolumn commands have been grouped (because multiColumnGrouping is set to $$1$$), and there are at least $$4$$ spaces after each aligned ampersand because spacesAfterAmpersand is set to $$4$$;
• in Listing 72 the \\ have not been aligned, because alignDoubleBackSlash is set to 0, otherwise the output is the same as Listing 68;
• in Listing 73 the \\ have been aligned, and because spacesBeforeDoubleBackSlash is set to 0, there are no spaces ahead of them; the output is otherwise the same as Listing 68;
• in Listing 74 the cells have been right-justified; note that cells above and below the \multicol statements have still been group correctly, because of the settings in Listing 60.

### 5.5.1. lookForAlignDelims: spacesBeforeAmpersand¶

The spacesBeforeAmpersand can be specified in a few different ways. The basic form is demonstrated in Listing 62, but we can customise the behaviour further by specifying if we would like this value to change if it encounters a leading blank column; that is, when the first column contains only zero-width entries. We refer to this as the advanced form.

We demonstrate this feature in relation to Listing 75; upon running the following command

latexindent.pl aligned1.tex -o=+-default


then we receive the default output given in Listing 76.

Listing 75 aligned1.tex
\begin{aligned}
& a & b, \\
& c & d.
\end{aligned}

Listing 76 aligned1-default.tex
\begin{aligned}
& a & b, \\
& c & d.
\end{aligned}


The settings in Listing 77Listing 80 are all equivlanent; we have used the not-yet discussed noAdditionalIndent field (see Section 5.8) which will assist in the demonstration in what follows.

Listing 77 sba1.yaml
noAdditionalIndent:
aligned: 1
lookForAlignDelims:
aligned: 1

Listing 78 sba2.yaml
noAdditionalIndent:
aligned: 1
lookForAlignDelims:
aligned:
spacesBeforeAmpersand: 1

Listing 79 sba3.yaml
noAdditionalIndent:
aligned: 1
lookForAlignDelims:
aligned:
spacesBeforeAmpersand:
default: 1

Listing 80 sba4.yaml
noAdditionalIndent:
aligned: 1
lookForAlignDelims:
aligned:
spacesBeforeAmpersand:


Upon running the following commands

latexindent.pl aligned1.tex -l sba1.yaml
latexindent.pl aligned1.tex -l sba2.yaml
latexindent.pl aligned1.tex -l sba3.yaml
latexindent.pl aligned1.tex -l sba4.yaml


then we receive the (same) output given in Listing 81; we note that there is one space before each ampersand.

Listing 81 aligned1-mod1.tex
\begin{aligned}
& a & b, \\
& c & d.
\end{aligned}


We note in particular:

• Listing 77 demonstrates the basic form for lookForAlignDelims; in this case, the default values are specified as in Listing 58;

• Listing 78 demonstrates the advanced form for lookForAlignDelims and specified spacesBeforeAmpersand. The default value is 1;

• Listing 79 demonstrates the new advanced way to specify spacesBeforeAmpersand, and for us to set the default value that sets the number of spaces before ampersands which are not in leading blank columns. The default value is 1.

We note that leadingBlankColumn has not been specified in Listing 79, and it will inherit the value from default;

• Listing 80 demonstrates spaces to be used before amperands for leading blank columns. We note that default has not been specified, and it will be set to 1 by default.

We can customise the space before the ampersand in the leading blank column of Listing 81 by using either of Listing 82 and Listing 83, which are equivalent.

Listing 82 sba5.yaml
noAdditionalIndent:
aligned: 1
lookForAlignDelims:
aligned:
spacesBeforeAmpersand:

Listing 83 sba6.yaml
noAdditionalIndent:
aligned: 1
lookForAlignDelims:
aligned:
spacesBeforeAmpersand:
default: 1


Upon running

latexindent.pl aligned1.tex -l sba5.yaml
latexindent.pl aligned1.tex -l sba6.yaml


then we receive the (same) output given in Listing 84. We note that the space before the ampersand in the leading blank column has been set to 0 by Listing 83.

We can demonstrated this feature further using the settings in Listing 86 which give the output in Listing 85.

Listing 84 aligned1-mod5.tex
\begin{aligned}
& a & b, \\
& c & d.
\end{aligned}

Listing 85 aligned1.tex using Listing 86
\begin{aligned}
& a& b, \\
& c& d.
\end{aligned}

Listing 86 sba7.yaml
noAdditionalIndent:
aligned: 1
lookForAlignDelims:
aligned:
spacesBeforeAmpersand:
default: 0


### 5.5.2. lookForAlignDelims: alignFinalDoubleBackSlash¶

We explore the alignFinalDoubleBackSlash feature by using the file in Listing 87. Upon running the following commands

latexindent.pl tabular4.tex -o=+-default
latexindent.pl tabular4.tex -o=+-FDBS -y="lookForAlignDelims:tabular:alignFinalDoubleBackSlash:1"


then we receive the respective outputs given in Listing 88 and Listing 89.

Listing 87 tabular4.tex
\begin{tabular}{lc}
Name & \shortstack{Hi \\ Lo} \\
Foo  & Bar            \\
\end{tabular}

Listing 88 tabular4-default.tex
\begin{tabular}{lc}
Name & \shortstack{Hi \\ Lo} \\
Foo  & Bar            \\
\end{tabular}

Listing 89 tabular4-FDBS.tex
\begin{tabular}{lc}
Name & \shortstack{Hi \\ Lo} \\
Foo  & Bar                   \\
\end{tabular}


We note that in:

• Listing 88, by default, the first set of double back slashes in the first row of the tabular environment have been used for alignment;
• Listing 89, the final set of double back slashes in the first row have been used, because we specified alignFinalDoubleBackSlash as 1.

As of Version 3.0, the alignment routine works on mandatory and optional arguments within commands, and also within ‘special’ code blocks (see specialBeginEnd on page yaml:specialBeginEnd); for example, assuming that you have a command called \matrix and that it is populated within lookForAlignDelims (which it is, by default), and that you run the command

latexindent.pl matrix1.tex


then the before-and-after results shown in Listing 90 and Listing 91 are achievable by default.

Listing 90 matrix1.tex
\matrix [
1&2   &3\\
4&5&6]{
7&8   &9\\
10&11&12
}

Listing 91 matrix1.tex default output
\matrix [
1 & 2 & 3 \\
4 & 5 & 6]{
7  & 8  & 9  \\
10 & 11 & 12
}


If you have blocks of code that you wish to align at the & character that are not wrapped in, for example, \begin{tabular}\end{tabular}, then you can use the mark up illustrated in Listing 92; the default output is shown in Listing 93. Note that the %* must be next to each other, but that there can be any number of spaces (possibly none) between the * and \begin{tabular}; note also that you may use any environment name that you have specified in lookForAlignDelims.

Listing 92 align-block.tex
%* \begin{tabular}
1 & 2 & 3 & 4 \\
5 &   & 6 &   \\
%* \end{tabular}

Listing 93 align-block.tex default output
%* \begin{tabular}
1 & 2 & 3 & 4 \\
5 &   & 6 &   \\
%* \end{tabular}


With reference to Table 2 and the, yet undiscussed, fields of noAdditionalIndent and indentRules (see Section 5.8), these comment-marked blocks are considered environments.

### 5.5.3. lookForAlignDelims: the dontMeasure feature¶

The lookForAlignDelims field can, optionally, receive the dontMeasure option which can be specified in a few different ways. We will explore this feature in relation to the code given in Listing 94; the default output is shown in Listing 95.

Listing 94 tabular-DM.tex
\begin{tabular}{cccc}
aaaaaa&bbbbb&ccc&dd\\
11&2&33&4\\
5&66&7&8
\end{tabular}

Listing 95 tabular-DM.tex default output
\begin{tabular}{cccc}
aaaaaa & bbbbb & ccc & dd \\
11     & 2     & 33  & 4  \\
5      & 66    & 7   & 8
\end{tabular}


The dontMeasure field can be specified as largest, and in which case, the largest element will not be measured; with reference to the YAML file given in Listing 97, we can run the command

latexindent.pl tabular-DM.tex -l=dontMeasure1.yaml


and receive the output given in Listing 96.

Listing 96 tabular-DM.tex using Listing 97
\begin{tabular}{cccc}
aaaaaa & bbbbb & ccc & dd \\
11 & 2  & 33 & 4          \\
5  & 66 & 7  & 8
\end{tabular}

Listing 97 dontMeasure1.yaml
lookForAlignDelims:
tabular:
dontMeasure: largest


We note that the largest column entries have not contributed to the measuring routine.

The dontMeasure field can also be specified in the form demonstrated in Listing 99. On running the following commands,

latexindent.pl tabular-DM.tex -l=dontMeasure2.yaml


we receive the output in Listing 98.

Listing 98 tabular-DM.tex using Listing 99 or Listing 101
\begin{tabular}{cccc}
aaaaaa & bbbbb & ccc & dd \\
11 & 2  & 33 & 4          \\
5  & 66 & 7  & 8
\end{tabular}

Listing 99 dontMeasure2.yaml
lookForAlignDelims:
tabular:
dontMeasure:
- aaaaaa
- bbbbb
- ccc
- dd


We note that in Listing 99 we have specified entries not to be measured, one entry per line.

The dontMeasure field can also be specified in the forms demonstrated in Listing 101 and Listing 102. Upon running the commands

latexindent.pl tabular-DM.tex -l=dontMeasure3.yaml
latexindent.pl tabular-DM.tex -l=dontMeasure4.yaml


we receive the output given in Listing 100

Listing 100 tabular-DM.tex using Listing 101 or Listing 101
\begin{tabular}{cccc}
aaaaaa & bbbbb & ccc & dd \\
11 & 2  & 33 & 4          \\
5  & 66 & 7  & 8
\end{tabular}

Listing 101 dontMeasure3.yaml
lookForAlignDelims:
tabular:
dontMeasure:
-
this: aaaaaa
applyTo: cell
-
this: bbbbb
- ccc
- dd

Listing 102 dontMeasure4.yaml
lookForAlignDelims:
tabular:
dontMeasure:
-
regex: [a-z]
applyTo: cell


We note that in:

• Listing 101 we have specified entries not to be measured, each one has a string in the this field, together with an optional specification of applyTo as cell;
• Listing 102 we have specified entries not to be measured as a regular expression using the regex field, together with an optional specification of applyTo as cell field, together with an optional specification of applyTo as cell.

In both cases, the default value of applyTo is cell, and does not need to be specified.

We may also specify the applyTo field as row, a demonstration of which is given in Listing 104; upon running

latexindent.pl tabular-DM.tex -l=dontMeasure5.yaml


we receive the output in Listing 103.

Listing 103 tabular-DM.tex using Listing 104
\begin{tabular}{cccc}
aaaaaa & bbbbb & ccc & dd \\
11 & 2  & 33 & 4          \\
5  & 66 & 7  & 8
\end{tabular}

Listing 104 dontMeasure5.yaml
lookForAlignDelims:
tabular:
dontMeasure:
-
this: aaaaaa&bbbbb&ccc&dd\\
applyTo: row


Finally, the applyTo field can be specified as row, together with a regex expression. For example, for the settings given in Listing 106, upon running

latexindent.pl tabular-DM.tex -l=dontMeasure6.yaml


we receive the output in Listing 105.

Listing 105 tabular-DM.tex using Listing 106
\begin{tabular}{cccc}
aaaaaa & bbbbb & ccc & dd \\
11 & 2  & 33 & 4          \\
5  & 66 & 7  & 8
\end{tabular}

Listing 106 dontMeasure6.yaml
lookForAlignDelims:
tabular:
dontMeasure:
-
regex: [a-z]
applyTo: row


### 5.5.4. lookForAlignDelims: the delimiterRegEx and delimiterJustification feature¶

The delimiter alignment will, by default, align code blocks at the ampersand character. The behaviour is controlled by the delimiterRegEx field within lookForAlignDelims; the default value is (?<!\\)(&)*, which can be read as: an ampersand, as long as it is not immediately preceeded by a backslash.

Warning

Important: note the ‘capturing’ parenthesis in the (&) which are necessary; if you intend to customise this field, then be sure to include them appropriately.

We demonstrate how to customise this with respect to the code given in Listing 107; the default output from latexindent.pl is given in Listing 108.

Listing 107 tabbing.tex
\begin{tabbing}
aa \=   bb \= cc \= dd \= ee \\
\>2\> 1 \> 7 \> 3 \\
\>3 \> 2\>8\> 3 \\
\>4 \>2 \\
\end{tabbing}

Listing 108 tabbing.tex default output
\begin{tabbing}
aa \=   bb \= cc \= dd \= ee \\
\>2\> 1 \> 7 \> 3 \\
\>3 \> 2\>8\> 3 \\
\>4 \>2 \\
\end{tabbing}


Let’s say that we wish to align the code at either the \= or \>. We employ the settings given in Listing 110 and run the command

latexindent.pl tabbing.tex -l=delimiterRegEx1.yaml


to receive the output given in Listing 109.

Listing 109 tabbing.tex using Listing 110
\begin{tabbing}
aa \= bb \= cc \= dd \= ee \\
\> 2  \> 1  \> 7  \> 3  \\
\> 3  \> 2  \> 8  \> 3  \\
\> 4  \> 2              \\
\end{tabbing}

Listing 110 delimiterRegEx1.yaml
lookForAlignDelims:
tabbing:
delimiterRegEx: '(\?:=|>))'  We note that: • in Listing 109 the code has been aligned, as intended, at both the \= and \>; • in Listing 110 we have heeded the warning and captured the expression using grouping parenthesis, specified a backslash using \\ and said that it must be followed by either = or >. We can explore delimiterRegEx a little further using the settings in Listing 112 and run the command latexindent.pl tabbing.tex -l=delimiterRegEx2.yaml  to receive the output given in Listing 111. Listing 111 tabbing.tex using Listing 112 \begin{tabbing} aa \= bb \= cc \= dd \= ee \\ \> 2 \> 1 \> 7 \> 3 \\ \> 3 \> 2 \> 8 \> 3 \\ \> 4 \> 2 \\ \end{tabbing}  Listing 112 delimiterRegEx2.yaml lookForAlignDelims: tabbing: delimiterRegEx: '(\\>)'  We note that only the \> have been aligned. Of course, the other lookForAlignDelims options can be used alongside the delimiterRegEx; regardless of the type of delimiter being used (ampersand or anything else), the fields from Listing 58 remain the same; for example, using the settings in Listing 114, and running latexindent.pl tabbing.tex -l=delimiterRegEx3.yaml  to receive the output given in Listing 113. Listing 113 tabbing.tex using Listing 114 \begin{tabbing} aa\=bb\=cc\=dd\=ee \\ \>2 \>1 \>7 \>3 \\ \>3 \>2 \>8 \>3 \\ \>4 \>2 \\ \end{tabbing}  Listing 114 delimiterRegEx3.yaml lookForAlignDelims: tabbing: delimiterRegEx: '(\\(?:=|>))' spacesBeforeAmpersand: 0 spacesAfterAmpersand: 0  It is possible that delimiters specified within delimiterRegEx can be of different lengths. Consider the file in Listing 115, and associated YAML in Listing 117. Note that the Listing 117 specifies the option for the delimiter to be either # or \>, which are different lengths. Upon running the command latexindent.pl tabbing1.tex -l=delimiterRegEx4.yaml -o=+-mod4  we receive the output in Listing 116. Listing 115 tabbing1.tex \begin{tabbing} 1#22\>333\\ xxx#aaa#yyyyy\\ .##&\\ \end{tabbing}  Listing 116 tabbing1-mod4.tex \begin{tabbing} 1 # 22 \> 333 \\ xxx # aaa # yyyyy \\ . # # & \\ \end{tabbing}  Listing 117 delimiterRegEx4.yaml lookForAlignDelims: tabbing: delimiterRegEx: '(#|\\>)'  You can set the delimiter justification as either left (default) or right, which will only have effect when delimiters in the same column have different lengths. Using the settings in Listing 119 and running the command latexindent.pl tabbing1.tex -l=delimiterRegEx5.yaml -o=+-mod5  gives the output in Listing 118. Listing 118 tabbing1-mod5.tex \begin{tabbing} 1 # 22 \> 333 \\ xxx # aaa # yyyyy \\ . # # & \\ \end{tabbing}  Listing 119 delimiterRegEx5.yaml lookForAlignDelims: tabbing: delimiterRegEx: '(#|\\>)' delimiterJustification: right  Note that in Listing 118 the second set of delimiters have been right aligned – it is quite subtle! ### 5.5.5. lookForAlignDelims: lookForChildCodeBlocks¶ There may be scenarios in which you would prefer to instruct latexindent.pl not to search for child blocks; in which case setting lookForChildCodeBlocks to 0 may be a good way to proceed. Using the settings from Listing 97 on the file in Listing 120 and running the command latexindent.pl tabular-DM-1.tex -l=dontMeasure1.yaml -o=+-mod1  gives the output in Listing 121. Listing 120 tabular-DM-1.tex \begin{tabular}{cc} 1&2\only<2->{\\ 3&4} \end{tabular}  Listing 121 tabular-DM-1-mod1.tex \begin{tabular}{cc} 1 & 2\only<2->{ \\ 3 & 4} \end{tabular}  We can improve the output from Listing 121 by employing the settings in Listing 123 latexindent.pl tabular-DM-1.tex -l=dontMeasure1a.yaml -o=+-mod1a  which gives the output in Listing 123. Listing 122 tabular-DM-1-mod1a.tex \begin{tabular}{cc} 1 & 2\only<2->{ \\ 3 & 4} \end{tabular}  Listing 123 dontMeasure1a.yaml lookForAlignDelims: tabular: dontMeasure: largest lookForChildCodeBlocks: 0  ## 5.6. Indent after items, specials and headings¶ indentAfterItems:fields The environment names specified in indentAfterItems tell latexindent.pl to look for \item commands; if these switches are set to 1 then indentation will be performed so as indent the code after each item. A demonstration is given in Listing 125 and Listing 126 Listing 124 indentAfterItems  234 235 236 237 238 239 240 241 indentAfterItems: itemize: 1 itemize*: 1 enumerate: 1 enumerate*: 1 description: 1 description*: 1 list: 1  Listing 125 items1.tex \begin{itemize} \item some text here some more text here some more text here \item another item some more text here \end{itemize}  Listing 126 items1.tex default output \begin{itemize} \item some text here some more text here some more text here \item another item some more text here \end{itemize}  itemNames:fields If you have your own item commands (perhaps you prefer to use myitem, for example) then you can put populate them in itemNames. For example, users of the exam document class might like to add parts to indentAfterItems and part to itemNames to their user settings (see Section 4 for details of how to configure user settings, and Listing 29 in particular .) Listing 127 itemNames  247 248 249 itemNames: item: 1 myitem: 1  specialBeginEnd:fields The fields specified in specialBeginEnd are, in their default state, focused on math mode begin and end statements, but there is no requirement for this to be the case; Listing 128 shows the default settings of specialBeginEnd. Listing 128 specialBeginEnd  253 254 255 256 257 258 259 260 261 262 263 264 265 266 specialBeginEnd: displayMath: begin: '\\$' end: '\\$' lookForThis: 1 inlineMath: begin: '(? The field displayMath represents $...$, inlineMath represents ... and displayMathTex represents .... You can, of course, rename these in your own YAML files (see Section 4.2); indeed, you might like to set up your own special begin and end statements. A demonstration of the before-and-after results are shown in Listing 129 and Listing 130. Listing 129 special1.tex before The function f has formula $f(x)=x^2.$ If you like splitting dollars,  g(x)=f(2x)   Listing 130 special1.tex default output The function f has formula $f(x)=x^2.$ If you like splitting dollars,  g(x)=f(2x)   For each field, lookForThis is set to 1 by default, which means that latexindent.pl will look for this pattern; you can tell latexindent.pl not to look for the pattern, by setting lookForThis to 0. There are examples in which it is advantageous to search for specialBeginEnd fields before searching for commands, and the specialBeforeCommand switch controls this behaviour. For example, consider the file shown in Listing 131. Listing 131 specialLR.tex \begin{equation} \left[ \sqrt{ a+b } \right] \end{equation}  Now consider the YAML files shown in Listing 132 and Listing 133 Listing 132 specialsLeftRight.yaml specialBeginEnd: leftRightSquare: begin: '\\left$' end: '\\right$' lookForThis: 1  Listing 133 specialBeforeCommand.yaml specialBeginEnd: specialBeforeCommand: 1  Upon running the following commands latexindent.pl specialLR.tex -l=specialsLeftRight.yaml latexindent.pl specialLR.tex -l=specialsLeftRight.yaml,specialBeforeCommand.yaml  we receive the respective outputs in Listing 134 and Listing 135. Listing 134 specialLR.tex using Listing 132 \begin{equation} \left[ \sqrt{ a+b } \right] \end{equation}  Listing 135 specialLR.tex using Listing 132 and Listing 133 \begin{equation} \left[ \sqrt{ a+b } \right] \end{equation}  Notice that in: • Listing 134 the \left has been treated as a command, with one optional argument; • Listing 135 the specialBeginEnd pattern in Listing 132 has been obeyed because Listing 133 specifies that the specialBeginEnd should be sought before commands. You can,optionally, specify the middle field for anything that you specify in specialBeginEnd. For example, let’s consider the .tex file in Listing 136. Listing 136 special2.tex \If something 0 \ElsIf something 1 \ElsIf something 2 \ElsIf something 3 \Else something 4 \EndIf  Upon saving the YAML settings in Listing 137 and Listing 139 and running the commands latexindent.pl special2.tex -l=middle latexindent.pl special2.tex -l=middle1  then we obtain the output given in Listing 138 and Listing 140. Listing 137 middle.yaml specialBeginEnd: If: begin: '\\If' middle: '\\ElsIf' end: '\\EndIf' lookForThis: 1  Listing 138 special2.tex using Listing 137 \If something 0 \ElsIf something 1 \ElsIf something 2 \ElsIf something 3 \Else something 4 \EndIf  Listing 139 middle1.yaml specialBeginEnd: If: begin: '\\If' middle: - '\\ElsIf' - '\\Else' end: '\\EndIf' lookForThis: 1  Listing 140 special2.tex using Listing 139 \If something 0 \ElsIf something 1 \ElsIf something 2 \ElsIf something 3 \Else something 4 \EndIf  We note that: • in Listing 138 the bodies of each of the Elsif statements have been indented appropriately; • the Else statement has not been indented appropriately in Listing 138 – read on! • we have specified multiple settings for the middle field using the syntax demonstrated in Listing 139 so that the body of the Else statement has been indented appropriately in Listing 140. You may specify fields in specialBeginEnd to be treated as verbatim code blocks by changing lookForThis to be verbatim. For example, beginning with the code in Listing 142 and the YAML in Listing 141, and running latexindent.pl special3.tex -l=special-verb1  then the output in Listing 142 is unchanged. Listing 141 special-verb1.yaml specialBeginEnd: displayMath: lookForThis: verbatim  Listing 142 special3.tex and output using Listing 141 $special code blocks can be treated as verbatim$  We can combine the specialBeginEnd with the lookForAlignDelims feature. We begin with the code in Listing 143. Listing 143 special-align.tex \begin{tikzpicture} \path (A) edge node {0,1,L}(B) edge node {1,1,R} (C) (B) edge [loop above]node {1,1,L}(B) edge node {0,1,L}(C) (C) edge node {0,1,L}(D) edge [bend left]node {1,0,R}(E) (D) edge[loop below] node {1,1,R}(D) edge node {0,1,R}(A) (E) edge[bend left] node {1,0,R} (A); \end{tikzpicture}  Let’s assume that our goal is to align the code at the edge and node text; we employ the code given in Listing 144 and run the command latexindent.pl special-align.tex -l edge-node1.yaml -o=+-mod1  to receive the output in Listing 145. Listing 144 edge-node1.yaml specialBeginEnd: path: begin: '\\path' end: ';' lookForThis: 1 specialBeforeCommand: 1 lookForAlignDelims: path: delimiterRegEx: '(edge|node)'  Listing 145 special-align.tex using Listing 144 \begin{tikzpicture} \path (A) edge node {0,1,L}(B) edge node {1,1,R} (C) (B) edge [loop above] node {1,1,L}(B) edge node {0,1,L}(C) (C) edge node {0,1,L}(D) edge [bend left] node {1,0,R}(E) (D) edge [loop below] node {1,1,R}(D) edge node {0,1,R}(A) (E) edge [bend left] node {1,0,R} (A); \end{tikzpicture}  The output in Listing 145 is not quite ideal. We can tweak the settings within Listing 144 in order to improve the output; in particular, we employ the code in Listing 146 and run the command latexindent.pl special-align.tex -l edge-node2.yaml -o=+-mod2  to receive the output in Listing 147. Listing 146 edge-node2.yaml specialBeginEnd: path: begin: '\\path' end: ';' specialBeforeCommand: 1 lookForAlignDelims: path: delimiterRegEx: '(edge|node\h*\{[0-9,A-Z]+\})'  Listing 147 special-align.tex using Listing 146 \begin{tikzpicture} \path (A) edge node {0,1,L} (B) edge node {1,1,R} (C) (B) edge [loop above] node {1,1,L} (B) edge node {0,1,L} (C) (C) edge node {0,1,L} (D) edge [bend left] node {1,0,R} (E) (D) edge [loop below] node {1,1,R} (D) edge node {0,1,R} (A) (E) edge [bend left] node {1,0,R} (A); \end{tikzpicture}  The lookForThis field can be considered optional; by default, it is assumed to be 1, which is demonstrated in Listing 146. indentAfterHeadings:fields This field enables the user to specify indentation rules that take effect after heading commands such as \part, \chapter, \section, \subsection*, or indeed any user-specified command written in this field. [2] Listing 148 indentAfterHeadings  276 277 278 279 280 281 282 283 284 285 indentAfterHeadings: part: indentAfterThisHeading: 0 level: 1 chapter: indentAfterThisHeading: 0 level: 2 section: indentAfterThisHeading: 0 level: 3  The default settings do not place indentation after a heading, but you can easily switch them on by changing indentAfterThisHeading from 0 to 1. The level field tells latexindent.pl the hierarchy of the heading structure in your document. You might, for example, like to have both section and subsection set with level: 3 because you do not want the indentation to go too deep. You can add any of your own custom heading commands to this field, specifying the level as appropriate. You can also specify your own indentation in indentRules (see Section 5.8); you will find the default indentRules contains chapter: " " which tells latexindent.pl simply to use a space character after chapter headings (once indent is set to 1 for chapter). For example, assuming that you have the code in Listing 149 saved into headings1.yaml, and that you have the text from Listing 150 saved into headings1.tex. Listing 149 headings1.yaml indentAfterHeadings: subsection: indentAfterThisHeading: 1 level: 1 paragraph: indentAfterThisHeading: 1 level: 2  Listing 150 headings1.tex \subsection{subsection title} subsection text subsection text \paragraph{paragraph title} paragraph text paragraph text \paragraph{paragraph title} paragraph text paragraph text  If you run the command latexindent.pl headings1.tex -l=headings1.yaml  then you should receive the output given in Listing 151. Listing 151 headings1.tex using Listing 149 \subsection{subsection title} subsection text subsection text \paragraph{paragraph title} paragraph text paragraph text \paragraph{paragraph title} paragraph text paragraph text  Listing 152 headings1.tex second modification \subsection{subsection title} subsection text subsection text \paragraph{paragraph title} paragraph text paragraph text \paragraph{paragraph title} paragraph text paragraph text  Now say that you modify the YAML from Listing 149 so that the paragraph level is 1; after running latexindent.pl headings1.tex -l=headings1.yaml  you should receive the code given in Listing 152; notice that the paragraph and subsection are at the same indentation level. maximumIndentation:horizontal space You can control the maximum indentation given to your file by specifying the maximumIndentation field as horizontal space (but not including tabs). This feature uses the Text::Tabs module (“Text::Tabs Perl Module” n.d.), and is off by default. For example, consider the example shown in Listing 153 together with the default output shown in Listing 154. Listing 153 mult-nested.tex \begin{one} one \begin{two} two \begin{three} three \begin{four} four \end{four} \end{three} \end{two} \end{one}  Listing 154 mult-nested.tex default output \begin{one} one \begin{two} two \begin{three} three \begin{four} four \end{four} \end{three} \end{two} \end{one}  Now say that, for example, you have the max-indentation1.yaml from Listing 155 and that you run the following command: latexindent.pl mult-nested.tex -l=max-indentation1  You should receive the output shown in Listing 156. Listing 155 max-indentation1.yaml maximumIndentation: " "  Listing 156 mult-nested.tex using Listing 155 \begin{one} one \begin{two} two \begin{three} three \begin{four} four \end{four} \end{three} \end{two} \end{one}  Comparing the output in Listing 154 and Listing 156 we notice that the (default) tabs of indentation have been replaced by a single space. In general, when using the maximumIndentation feature, any leading tabs will be replaced by equivalent spaces except, of course, those found in verbatimEnvironments (see Listing 34) or noIndentBlock (see Listing 40). ## 5.7. The code blocks known latexindent.pl¶ As of Version 3.0, latexindent.pl processes documents using code blocks; each of these are shown in Table 2. Table 2 Code blocks known to latexindent.pl Code block characters allowed in name example environments !a-zA-Z@*0-9_\! \begin{myenv}body of myenv\end{myenv} optionalArguments inherits name from parent (e.g environment name) [opt arg text] mandatoryArguments inherits name from parent (e.g environment name) {mand arg text} commands +a-zA-Z@\*0-9_\: \mycommand<arguments> keyEqualsValuesBracesBrackets a-zA-Z@\*0-9_\/.\h\{\}:\#- my key/.style=<arguments> namedGroupingBracesBrackets 0-9\.a-zA-Z@\*>< in<arguments> UnNamedGroupingBracesBrackets No name! { or [ or , or \& or ) or ( or  followed by <arguments> ifElseFi @a-zA-Z but must begin with either \if of \@if \ifnum......\else...\fi items User specified, see Listing 124 and Listing 127 \begin{enumerate} \item ...\end{enumerate} specialBeginEnd User specified, see Listing 128 $...$ afterHeading User specified, see Listing 148 \chapter{title} ...\section{title} filecontents User specified, see Listing 50 \begin{filecontents}...\end{filecontents} We will refer to these code blocks in what follows. Note that the fine tuning of the definition of the code blocks detailed in Table 2 is discussed in Section 9. ## 5.8. noAdditionalIndent and indentRules¶ latexindent.pl operates on files by looking for code blocks, as detailed in Section 5.7; for each type of code block in Table 2 (which we will call a <thing> in what follows) it searches YAML fields for information in the following order: 1. noAdditionalIndent for the name of the current <thing>; 2. indentRules for the name of the current <thing>; 3. noAdditionalIndentGlobal for the type of the current <thing>; 4. indentRulesGlobal for the type of the current <thing>. Using the above list, the first piece of information to be found will be used; failing that, the value of defaultIndent is used. If information is found in multiple fields, the first one according to the list above will be used; for example, if information is present in both indentRules and in noAdditionalIndentGlobal, then the information from indentRules takes priority. We now present details for the different type of code blocks known to latexindent.pl, as detailed in Table 2; for reference, there follows a list of the code blocks covered. ### 5.8.1. Environments and their arguments¶ There are a few different YAML switches governing the indentation of environments; let’s start with the code shown in Listing 157. Listing 157 myenv.tex \begin{outer} \begin{myenv} body of environment body of environment body of environment \end{myenv} \end{outer}  noAdditionalIndent:fields If we do not wish myenv to receive any additional indentation, we have a few choices available to us, as demonstrated in Listing 158 and Listing 159. Listing 158 myenv-noAdd1.yaml noAdditionalIndent: myenv: 1  Listing 159 myenv-noAdd2.yaml noAdditionalIndent: myenv: body: 1  On applying either of the following commands, latexindent.pl myenv.tex -l myenv-noAdd1.yaml latexindent.pl myenv.tex -l myenv-noAdd2.yaml  we obtain the output given in Listing 160; note in particular that the environment myenv has not received any additional indentation, but that the outer environment has still received indentation. Listing 160 myenv.tex output (using either Listing 158 or Listing 159) \begin{outer} \begin{myenv} body of environment body of environment body of environment \end{myenv} \end{outer}  Upon changing the YAML files to those shown in Listing 161 and Listing 162, and running either latexindent.pl myenv.tex -l myenv-noAdd3.yaml latexindent.pl myenv.tex -l myenv-noAdd4.yaml  we obtain the output given in Listing 163. Listing 161 myenv-noAdd3.yaml noAdditionalIndent: myenv: 0  Listing 162 myenv-noAdd4.yaml noAdditionalIndent: myenv: body: 0  Listing 163 myenv.tex output (using either Listing 161 or Listing 162) \begin{outer} \begin{myenv} body of environment body of environment body of environment \end{myenv} \end{outer}  Let’s now allow myenv to have some optional and mandatory arguments, as in Listing 164. Listing 164 myenv-args.tex \begin{outer} \begin{myenv}[% optional argument text optional argument text]% { mandatory argument text mandatory argument text} body of environment body of environment body of environment \end{myenv} \end{outer}  Upon running latexindent.pl -l=myenv-noAdd1.yaml myenv-args.tex  we obtain the output shown in Listing 165; note that the optional argument, mandatory argument and body all have received no additional indent. This is because, when noAdditionalIndent is specified in ‘scalar’ form (as in Listing 158), then all parts of the environment (body, optional and mandatory arguments) are assumed to want no additional indent. Listing 165 myenv-args.tex using Listing 158 \begin{outer} \begin{myenv}[% optional argument text optional argument text]% { mandatory argument text mandatory argument text} body of environment body of environment body of environment \end{myenv} \end{outer}  We may customise noAdditionalIndent for optional and mandatory arguments of the myenv environment, as shown in, for example, Listing 166 and Listing 167. Listing 166 myenv-noAdd5.yaml noAdditionalIndent: myenv: body: 0 optionalArguments: 1 mandatoryArguments: 0  Listing 167 myenv-noAdd6.yaml noAdditionalIndent: myenv: body: 0 optionalArguments: 0 mandatoryArguments: 1  Upon running latexindent.pl myenv.tex -l myenv-noAdd5.yaml latexindent.pl myenv.tex -l myenv-noAdd6.yaml  we obtain the respective outputs given in Listing 168 and Listing 169. Note that in Listing 168 the text for the optional argument has not received any additional indentation, and that in Listing 169 the mandatory argument has not received any additional indentation; in both cases, the body has not received any additional indentation. Listing 168 myenv-args.tex using Listing 166 \begin{outer} \begin{myenv}[% optional argument text optional argument text]% { mandatory argument text mandatory argument text} body of environment body of environment body of environment \end{myenv} \end{outer}  Listing 169 myenv-args.tex using Listing 167 \begin{outer} \begin{myenv}[% optional argument text optional argument text]% { mandatory argument text mandatory argument text} body of environment body of environment body of environment \end{myenv} \end{outer}  indentRules:fields We may also specify indentation rules for environment code blocks using the indentRules field; see, for example, Listing 170 and Listing 171. Listing 170 myenv-rules1.yaml indentRules: myenv: " "  Listing 171 myenv-rules2.yaml indentRules: myenv: body: " "  On applying either of the following commands, latexindent.pl myenv.tex -l myenv-rules1.yaml latexindent.pl myenv.tex -l myenv-rules2.yaml  we obtain the output given in Listing 172; note in particular that the environment myenv has received one tab (from the outer environment) plus three spaces from Listing 170 or Listing 171. Listing 172 myenv.tex output (using either Listing 170 or Listing 171) \begin{outer} \begin{myenv} body of environment body of environment body of environment \end{myenv} \end{outer}  If you specify a field in indentRules using anything other than horizontal space, it will be ignored. Returning to the example in Listing 164 that contains optional and mandatory arguments. Upon using Listing 170 as in latexindent.pl myenv-args.tex -l=myenv-rules1.yaml  we obtain the output in Listing 173; note that the body, optional argument and mandatory argument of myenv have all received the same customised indentation. Listing 173 myenv-args.tex using Listing 170 \begin{outer} \begin{myenv}[% optional argument text optional argument text]% { mandatory argument text mandatory argument text} body of environment body of environment body of environment \end{myenv} \end{outer}  You can specify different indentation rules for the different features using, for example, Listing 174 and Listing 175 Listing 174 myenv-rules3.yaml indentRules: myenv: body: " " optionalArguments: " "  Listing 175 myenv-rules4.yaml indentRules: myenv: body: " " mandatoryArguments: "\t\t"  After running latexindent.pl myenv-args.tex -l myenv-rules3.yaml latexindent.pl myenv-args.tex -l myenv-rules4.yaml  then we obtain the respective outputs given in Listing 176 and Listing 177. Listing 176 myenv-args.tex using Listing 174 \begin{outer} \begin{myenv}[% optional argument text optional argument text]% { mandatory argument text mandatory argument text} body of environment body of environment body of environment \end{myenv} \end{outer}  Listing 177 myenv-args.tex using Listing 175 \begin{outer} \begin{myenv}[% optional argument text optional argument text]% { mandatory argument text mandatory argument text} body of environment body of environment body of environment \end{myenv} \end{outer}  Note that in Listing 176, the optional argument has only received a single space of indentation, while the mandatory argument has received the default (tab) indentation; the environment body has received three spaces of indentation. In Listing 177, the optional argument has received the default (tab) indentation, the mandatory argument has received two tabs of indentation, and the body has received three spaces of indentation. noAdditionalIndentGlobal:fields Assuming that your environment name is not found within neither noAdditionalIndent nor indentRules, the next place that latexindent.pl will look is noAdditionalIndentGlobal, and in particular for the environments key (see Listing 178). Listing 178 noAdditionalIndentGlobal  334 335 noAdditionalIndentGlobal: environments: 0  Let’s say that you change the value of environments to 1 in Listing 178, and that you run latexindent.pl myenv-args.tex -l env-noAdditionalGlobal.yaml latexindent.pl myenv-args.tex -l myenv-rules1.yaml,env-noAdditionalGlobal.yaml  The respective output from these two commands are in Listing 179 and Listing 180; in Listing 179 notice that both environments receive no additional indentation but that the arguments of myenv still do receive indentation. In Listing 180 notice that the outer environment does not receive additional indentation, but because of the settings from myenv-rules1.yaml (in Listing 170), the myenv environment still does receive indentation. Listing 179 myenv-args.tex using Listing 178 \begin{outer} \begin{myenv}[% optional argument text optional argument text]% { mandatory argument text mandatory argument text} body of environment body of environment body of environment \end{myenv} \end{outer}  Listing 180 myenv-args.tex using Listing 178 and Listing 170 \begin{outer} \begin{myenv}[% optional argument text optional argument text]% { mandatory argument text mandatory argument text} body of environment body of environment body of environment \end{myenv} \end{outer}  In fact, noAdditionalIndentGlobal also contains keys that control the indentation of optional and mandatory arguments; on referencing Listing 181 and Listing 182 Listing 181 opt-args-no-add-glob.yaml noAdditionalIndentGlobal: optionalArguments: 1  Listing 182 mand-args-no-add-glob.yaml noAdditionalIndentGlobal: mandatoryArguments: 1  we may run the commands latexindent.pl myenv-args.tex -local opt-args-no-add-glob.yaml latexindent.pl myenv-args.tex -local mand-args-no-add-glob.yaml  which produces the respective outputs given in Listing 183 and Listing 184. Notice that in Listing 183 the optional argument has not received any additional indentation, and in Listing 184 the mandatory argument has not received any additional indentation. Listing 183 myenv-args.tex using Listing 181 \begin{outer} \begin{myenv}[% optional argument text optional argument text]% { mandatory argument text mandatory argument text} body of environment body of environment body of environment \end{myenv} \end{outer}  Listing 184 myenv-args.tex using Listing 182 \begin{outer} \begin{myenv}[% optional argument text optional argument text]% { mandatory argument text mandatory argument text} body of environment body of environment body of environment \end{myenv} \end{outer}  indentRulesGlobal:fields The final check that latexindent.pl will make is to look for indentRulesGlobal as detailed in Listing 185. Listing 185 indentRulesGlobal  350 351 indentRulesGlobal: environments: 0  If you change the environments field to anything involving horizontal space, say " ", and then run the following commands latexindent.pl myenv-args.tex -l env-indentRules.yaml latexindent.pl myenv-args.tex -l myenv-rules1.yaml,env-indentRules.yaml  then the respective output is shown in Listing 186 and Listing 187. Note that in Listing 186, both the environment blocks have received a single-space indentation, whereas in Listing 187 the outer environment has received single-space indentation (specified by indentRulesGlobal), but myenv has received " ", as specified by the particular indentRules for myenv Listing 170. Listing 186 myenv-args.tex using Listing 185 \begin{outer} \begin{myenv}[% optional argument text optional argument text]% { mandatory argument text mandatory argument text} body of environment body of environment body of environment \end{myenv} \end{outer}  Listing 187 myenv-args.tex using Listing 170 and Listing 185 \begin{outer} \begin{myenv}[% optional argument text optional argument text]% { mandatory argument text mandatory argument text} body of environment body of environment body of environment \end{myenv} \end{outer}  You can specify indentRulesGlobal for both optional and mandatory arguments, as detailed in Listing 188 and Listing 189 Listing 188 opt-args-indent-rules-glob.yaml indentRulesGlobal: optionalArguments: "\t\t"  Listing 189 mand-args-indent-rules-glob.yaml indentRulesGlobal: mandatoryArguments: "\t\t"  Upon running the following commands latexindent.pl myenv-args.tex -local opt-args-indent-rules-glob.yaml latexindent.pl myenv-args.tex -local mand-args-indent-rules-glob.yaml  we obtain the respective outputs in Listing 190 and Listing 191. Note that the optional argument in Listing 190 has received two tabs worth of indentation, while the mandatory argument has done so in Listing 191. Listing 190 myenv-args.tex using Listing 188 \begin{outer} \begin{myenv}[% optional argument text optional argument text]% { mandatory argument text mandatory argument text} body of environment body of environment body of environment \end{myenv} \end{outer}  Listing 191 myenv-args.tex using Listing 189 \begin{outer} \begin{myenv}[% optional argument text optional argument text]% { mandatory argument text mandatory argument text} body of environment body of environment body of environment \end{myenv} \end{outer}  ### 5.8.2. Environments with items¶ With reference to Listing 124 and Listing 127, some commands may contain item commands; for the purposes of this discussion, we will use the code from Listing 125. Assuming that you’ve populated itemNames with the name of your item, you can put the item name into noAdditionalIndent as in Listing 192, although a more efficient approach may be to change the relevant field in itemNames to 0. Similarly, you can customise the indentation that your item receives using indentRules, as in Listing 193 Listing 192 item-noAdd1.yaml noAdditionalIndent: item: 1 # itemNames: # item: 0  Listing 193 item-rules1.yaml indentRules: item: " "  Upon running the following commands latexindent.pl items1.tex -local item-noAdd1.yaml latexindent.pl items1.tex -local item-rules1.yaml  the respective outputs are given in Listing 194 and Listing 195; note that in Listing 194 that the text after each item has not received any additional indentation, and in Listing 195, the text after each item has received a single space of indentation, specified by Listing 193. Listing 194 items1.tex using Listing 192 \begin{itemize} \item some text here some more text here some more text here \item another item some more text here \end{itemize}  Listing 195 items1.tex using Listing 193 \begin{itemize} \item some text here some more text here some more text here \item another item some more text here \end{itemize}  Alternatively, you might like to populate noAdditionalIndentGlobal or indentRulesGlobal using the items key, as demonstrated in Listing 196 and Listing 197. Note that there is a need to ‘reset/remove’ the item field from indentRules in both cases (see the hierarchy description given on page sec:noadd-indent-rules) as the item command is a member of indentRules by default. Listing 196 items-noAdditionalGlobal.yaml indentRules: item: 0 noAdditionalIndentGlobal: items: 1  Listing 197 items-indentRulesGlobal.yaml indentRules: item: 0 indentRulesGlobal: items: " "  Upon running the following commands, latexindent.pl items1.tex -local items-noAdditionalGlobal.yaml latexindent.pl items1.tex -local items-indentRulesGlobal.yaml  the respective outputs from Listing 194 and Listing 195 are obtained; note, however, that all such item commands without their own individual noAdditionalIndent or indentRules settings would behave as in these listings. ### 5.8.3. Commands with arguments¶ Let’s begin with the simple example in Listing 198; when latexindent.pl operates on this file, the default output is shown in Listing 199. [3] Listing 198 mycommand.tex \mycommand { mand arg text mand arg text} [ opt arg text opt arg text ]  Listing 199 mycommand.tex default output \mycommand { mand arg text mand arg text} [ opt arg text opt arg text ]  As in the environment-based case (see Listing 158 and Listing 159) we may specify noAdditionalIndent either in ‘scalar’ form, or in ‘field’ form, as shown in Listing 200 and Listing 201 Listing 200 mycommand-noAdd1.yaml noAdditionalIndent: mycommand: 1  Listing 201 mycommand-noAdd2.yaml noAdditionalIndent: mycommand: body: 1  After running the following commands, latexindent.pl mycommand.tex -l mycommand-noAdd1.yaml latexindent.pl mycommand.tex -l mycommand-noAdd2.yaml  we receive the respective output given in Listing 202 and Listing 203 Listing 202 mycommand.tex using Listing 200 \mycommand { mand arg text mand arg text} [ opt arg text opt arg text ]  Listing 203 mycommand.tex using Listing 201 \mycommand { mand arg text mand arg text} [ opt arg text opt arg text ]  Note that in Listing 202 that the ‘body’, optional argument and mandatory argument have all received no additional indentation, while in Listing 203, only the ‘body’ has not received any additional indentation. We define the ‘body’ of a command as any lines following the command name that include its optional or mandatory arguments. We may further customise noAdditionalIndent for mycommand as we did in Listing 166 and Listing 167; explicit examples are given in Listing 204 and Listing 205. Listing 204 mycommand-noAdd3.yaml noAdditionalIndent: mycommand: body: 0 optionalArguments: 1 mandatoryArguments: 0  Listing 205 mycommand-noAdd4.yaml noAdditionalIndent: mycommand: body: 0 optionalArguments: 0 mandatoryArguments: 1  After running the following commands, latexindent.pl mycommand.tex -l mycommand-noAdd3.yaml latexindent.pl mycommand.tex -l mycommand-noAdd4.yaml  we receive the respective output given in Listing 206 and Listing 207. Listing 206 mycommand.tex using Listing 204 \mycommand { mand arg text mand arg text} [ opt arg text opt arg text ]  Listing 207 mycommand.tex using Listing 205 \mycommand { mand arg text mand arg text} [ opt arg text opt arg text ]  Attentive readers will note that the body of mycommand in both Listing 206 and Listing 207 has received no additional indent, even though body is explicitly set to 0 in both Listing 204 and Listing 205. This is because, by default, noAdditionalIndentGlobal for commands is set to 1 by default; this can be easily fixed as in Listing 208 and Listing 209. Listing 208 mycommand-noAdd5.yaml noAdditionalIndent: mycommand: body: 0 optionalArguments: 1 mandatoryArguments: 0 noAdditionalIndentGlobal: commands: 0  Listing 209 mycommand-noAdd6.yaml noAdditionalIndent: mycommand: body: 0 optionalArguments: 0 mandatoryArguments: 1 noAdditionalIndentGlobal: commands: 0  After running the following commands, latexindent.pl mycommand.tex -l mycommand-noAdd5.yaml latexindent.pl mycommand.tex -l mycommand-noAdd6.yaml  we receive the respective output given in Listing 210 and Listing 211. Listing 210 mycommand.tex using Listing 208 \mycommand { mand arg text mand arg text} [ opt arg text opt arg text ]  Listing 211 mycommand.tex using Listing 209 \mycommand { mand arg text mand arg text} [ opt arg text opt arg text ]  Both indentRules and indentRulesGlobal can be adjusted as they were for environment code blocks, as in Listing 174 and Listing 175 and Listing 185 and Listing 188 and Listing 189. ### 5.8.4. ifelsefi code blocks¶ Let’s use the simple example shown in Listing 212; when latexindent.pl operates on this file, the output as in Listing 213; note that the body of each of the \if statements have been indented, and that the \else statement has been accounted for correctly. Listing 212 ifelsefi1.tex \ifodd\radius \ifnum\radius<14 \pgfmathparse{100-(\radius)*4}; \else \pgfmathparse{200-(\radius)*3}; \fi\fi  Listing 213 ifelsefi1.tex default output \ifodd\radius \ifnum\radius<14 \pgfmathparse{100-(\radius)*4}; \else \pgfmathparse{200-(\radius)*3}; \fi\fi  It is recommended to specify noAdditionalIndent and indentRules in the ‘scalar’ form only for these type of code blocks, although the ‘field’ form would work, assuming that body was specified. Examples are shown in Listing 214 and Listing 215. Listing 214 ifnum-noAdd.yaml noAdditionalIndent: ifnum: 1  Listing 215 ifnum-indent-rules.yaml indentRules: ifnum: " "  After running the following commands, latexindent.pl ifelsefi1.tex -local ifnum-noAdd.yaml latexindent.pl ifelsefi1.tex -l ifnum-indent-rules.yaml  we receive the respective output given in Listing 216 and Listing 217; note that in Listing 216, the ifnum code block has not received any additional indentation, while in Listing 217, the ifnum code block has received one tab and two spaces of indentation. Listing 216 ifelsefi1.tex using Listing 214 \ifodd\radius \ifnum\radius<14 \pgfmathparse{100-(\radius)*4}; \else \pgfmathparse{200-(\radius)*3}; \fi\fi  Listing 217 ifelsefi1.tex using Listing 215 \ifodd\radius \ifnum\radius<14 \pgfmathparse{100-(\radius)*4}; \else \pgfmathparse{200-(\radius)*3}; \fi\fi  We may specify noAdditionalIndentGlobal and indentRulesGlobal as in Listing 218 and Listing 219. Listing 218 ifelsefi-noAdd-glob.yaml noAdditionalIndentGlobal: ifElseFi: 1  Listing 219 ifelsefi-indent-rules-global.yaml indentRulesGlobal: ifElseFi: " "  Upon running the following commands latexindent.pl ifelsefi1.tex -local ifelsefi-noAdd-glob.yaml latexindent.pl ifelsefi1.tex -l ifelsefi-indent-rules-global.yaml  we receive the outputs in Listing 220 and Listing 221; notice that in Listing 220 neither of the ifelsefi code blocks have received indentation, while in Listing 221 both code blocks have received a single space of indentation. Listing 220 ifelsefi1.tex using Listing 218 \ifodd\radius \ifnum\radius<14 \pgfmathparse{100-(\radius)*4}; \else \pgfmathparse{200-(\radius)*3}; \fi\fi  Listing 221 ifelsefi1.tex using Listing 219 \ifodd\radius \ifnum\radius<14 \pgfmathparse{100-(\radius)*4}; \else \pgfmathparse{200-(\radius)*3}; \fi\fi  We can further explore the treatment of ifElseFi code blocks in Listing 222, and the associated default output given in Listing 223; note, in particular, that the bodies of each of the ‘or statements’ have been indented. Listing 222 ifelsefi2.tex \ifcase#1 zero% \or one% \or two% \or three% \else default \fi  Listing 223 ifelsefi2.tex default output \ifcase#1 zero% \or one% \or two% \or three% \else default \fi  ### 5.8.5. specialBeginEnd code blocks¶ Let’s use the example from Listing 129 which has default output shown in Listing 130. It is recommended to specify noAdditionalIndent and indentRules in the ‘scalar’ form for these type of code blocks, although the ‘field’ form would work, assuming that body was specified. Examples are shown in Listing 224 and Listing 225. Listing 224 displayMath-noAdd.yaml noAdditionalIndent: displayMath: 1  Listing 225 displayMath-indent-rules.yaml indentRules: displayMath: "\t\t\t"  After running the following commands, latexindent.pl special1.tex -local displayMath-noAdd.yaml latexindent.pl special1.tex -l displayMath-indent-rules.yaml  we receive the respective output given in Listing 226 and Listing 227; note that in Listing 226, the displayMath code block has not received any additional indentation, while in Listing 227, the displayMath code block has received three tabs worth of indentation. Listing 226 special1.tex using Listing 224 The function f has formula $f(x)=x^2.$ If you like splitting dollars,  g(x)=f(2x)   Listing 227 special1.tex using Listing 225 The function f has formula $f(x)=x^2.$ If you like splitting dollars,  g(x)=f(2x)   We may specify noAdditionalIndentGlobal and indentRulesGlobal as in Listing 228 and Listing 229. Listing 228 special-noAdd-glob.yaml noAdditionalIndentGlobal: specialBeginEnd: 1  Listing 229 special-indent-rules-global.yaml indentRulesGlobal: specialBeginEnd: " "  Upon running the following commands latexindent.pl special1.tex -local special-noAdd-glob.yaml latexindent.pl special1.tex -l special-indent-rules-global.yaml  we receive the outputs in Listing 230 and Listing 231; notice that in Listing 230 neither of the special code blocks have received indentation, while in Listing 231 both code blocks have received a single space of indentation. Listing 230 special1.tex using Listing 228 The function f has formula $f(x)=x^2.$ If you like splitting dollars,  g(x)=f(2x)   Listing 231 special1.tex using Listing 229 The function f has formula $f(x)=x^2.$ If you like splitting dollars,  g(x)=f(2x)   ### 5.8.6. afterHeading code blocks¶ Let’s use the example Listing 232 for demonstration throughout this . As discussed on page lst:headings1, by default latexindent.pl will not add indentation after headings. Listing 232 headings2.tex \paragraph{paragraph title} paragraph text paragraph text  On using the YAML file in Listing 234 by running the command latexindent.pl headings2.tex -l headings3.yaml  we obtain the output in Listing 233. Note that the argument of paragraph has received (default) indentation, and that the body after the heading statement has received (default) indentation. Listing 233 headings2.tex using Listing 234 \paragraph{paragraph title} paragraph text paragraph text  Listing 234 headings3.yaml indentAfterHeadings: paragraph: indentAfterThisHeading: 1 level: 1  If we specify noAdditionalIndent as in Listing 236 and run the command latexindent.pl headings2.tex -l headings4.yaml  then we receive the output in Listing 235. Note that the arguments and the body after the heading of paragraph has received no additional indentation, because we have specified noAdditionalIndent in scalar form. Listing 235 headings2.tex using Listing 236 \paragraph{paragraph title} paragraph text paragraph text  Listing 236 headings4.yaml indentAfterHeadings: paragraph: indentAfterThisHeading: 1 level: 1 noAdditionalIndent: paragraph: 1  Similarly, if we specify indentRules as in Listing 238 and run analogous commands to those above, we receive the output in Listing 237; note that the body, mandatory argument and content after the heading of paragraph have all received three tabs worth of indentation. Listing 237 headings2.tex using Listing 238 \paragraph{paragraph title} paragraph text paragraph text  Listing 238 headings5.yaml indentAfterHeadings: paragraph: indentAfterThisHeading: 1 level: 1 indentRules: paragraph: "\t\t\t"  We may, instead, specify noAdditionalIndent in ‘field’ form, as in Listing 240 which gives the output in Listing 239. Listing 239 headings2.tex using Listing 240 \paragraph{paragraph title} paragraph text paragraph text  Listing 240 headings6.yaml indentAfterHeadings: paragraph: indentAfterThisHeading: 1 level: 1 noAdditionalIndent: paragraph: body: 0 mandatoryArguments: 0 afterHeading: 1  Analogously, we may specify indentRules as in Listing 242 which gives the output in Listing 241; note that mandatory argument text has only received a single space of indentation, while the body after the heading has received three tabs worth of indentation. Listing 241 headings2.tex using Listing 242 \paragraph{paragraph title} paragraph text paragraph text  Listing 242 headings7.yaml indentAfterHeadings: paragraph: indentAfterThisHeading: 1 level: 1 indentRules: paragraph: mandatoryArguments: " " afterHeading: "\t\t\t"  Finally, let’s consider noAdditionalIndentGlobal and indentRulesGlobal shown in Listing 244 and Listing 246 respectively, with respective output in Listing 243 and Listing 245. Note that in Listing 244 the mandatory argument of paragraph has received a (default) tab’s worth of indentation, while the body after the heading has received no additional indentation. Similarly, in Listing 245, the argument has received both a (default) tab plus two spaces of indentation (from the global rule specified in Listing 246), and the remaining body after paragraph has received just two spaces of indentation. Listing 243 headings2.tex using Listing 244 \paragraph{paragraph title} paragraph text paragraph text  Listing 244 headings8.yaml indentAfterHeadings: paragraph: indentAfterThisHeading: 1 level: 1 noAdditionalIndentGlobal: afterHeading: 1  Listing 245 headings2.tex using Listing 246 \paragraph{paragraph title} paragraph text paragraph text  Listing 246 headings9.yaml indentAfterHeadings: paragraph: indentAfterThisHeading: 1 level: 1 indentRulesGlobal: afterHeading: " "  ### 5.8.7. The remaining code blocks¶ Referencing the different types of code blocks in Table 2, we have a few code blocks yet to cover; these are very similar to the commands code block type covered comprehensively in Section 5.8.3, but a small discussion defining these remaining code blocks is necessary. #### 5.8.7.1. keyEqualsValuesBracesBrackets¶ latexindent.pl defines this type of code block by the following criteria: • it must immediately follow either { OR [ OR , with comments and blank lines allowed. • then it has a name made up of the characters detailed in Table 2; • then an \(= symbol;
• then at least one set of curly braces or square brackets (comments and line breaks allowed throughout).

See the keyEqualsValuesBracesBrackets: follow and keyEqualsValuesBracesBrackets: name fields of the fine tuning section in Listing 522

An example is shown in Listing 247, with the default output given in Listing 248.

Listing 247 pgfkeys1.tex
\pgfkeys{/tikz/.cd,
start coordinate/.initial={0,
\vertfactor},
}

Listing 248 pgfkeys1.tex default output
\pgfkeys{/tikz/.cd,
start coordinate/.initial={0,
\vertfactor},
}


In Listing 248, note that the maximum indentation is three tabs, and these come from:

• the \pgfkeys command’s mandatory argument;
• the start coordinate/.initial key’s mandatory argument;
• the start coordinate/.initial key’s body, which is defined as any lines following the name of the key that include its arguments. This is the part controlled by the body field for noAdditionalIndent and friends from page sec:noadd-indent-rules.

#### 5.8.7.2. namedGroupingBracesBrackets¶

This type of code block is mostly motivated by tikz-based code; we define this code block as follows:

• it must immediately follow either horizontal space OR one or more line breaks OR { OR [ OR $ OR ) OR ( • the name may contain the characters detailed in Table 2; • then at least one set of curly braces or square brackets (comments and line breaks allowed throughout). See the NamedGroupingBracesBrackets: follow and NamedGroupingBracesBrackets: name fields of the fine tuning section in Listing 522 A simple example is given in Listing 249, with default output in Listing 250. Listing 249 child1.tex \coordinate child[grow=down]{ edge from parent [antiparticle] node [above=3pt] {$C$} }  Listing 250 child1.tex default output \coordinate child[grow=down]{ edge from parent [antiparticle] node [above=3pt] {$C$} }  In particular, latexindent.pl considers child, parent and node all to be namedGroupingBracesBrackets [4]. Referencing Listing 250, note that the maximum indentation is two tabs, and these come from: • the child’s mandatory argument; • the child’s body, which is defined as any lines following the name of the namedGroupingBracesBrackets that include its arguments. This is the part controlled by the body field for noAdditionalIndent and friends from page sec:noadd-indent-rules. #### 5.8.7.3. UnNamedGroupingBracesBrackets¶ occur in a variety of situations; specifically, we define this type of code block as satisfying the following criteria: • it must immediately follow either { OR [ OR , OR & OR ) OR ( OR $;
• then at least one set of curly braces or square brackets (comments and line breaks allowed throughout).

See the UnNamedGroupingBracesBrackets: follow field of the fine tuning section in Listing 522

An example is shown in Listing 251 with default output give in Listing 252.

Listing 251 psforeach1.tex
\psforeach{\row}{%
{
{3,2.8,2.7,3,3.1}},%
{2.8,1,1.2,2,3},%
}

Listing 252 psforeach1.tex default output
\psforeach{\row}{%
{
{3,2.8,2.7,3,3.1}},%
{2.8,1,1.2,2,3},%
}


Referencing Listing 252, there are three sets of unnamed braces. Note also that the maximum value of indentation is three tabs, and these come from:

• the \psforeach command’s mandatory argument;
• the first un-named braces mandatory argument;
• the first un-named braces body, which we define as any lines following the first opening { or [ that defined the code block. This is the part controlled by the body field for noAdditionalIndent and friends from page sec:noadd-indent-rules.

Users wishing to customise the mandatory and/or optional arguments on a per-name basis for the UnNamedGroupingBracesBrackets should use always-un-named.

#### 5.8.7.4. filecontents¶

code blocks behave just as environments, except that neither arguments nor items are sought.

### 5.8.8. Summary¶

Having considered all of the different types of code blocks, the functions of the fields given in Listing 253 and Listing 254 should now make sense.

Listing 253 noAdditionalIndentGlobal
 334 335 336 337 338 339 340 341 342 343 344 345 346 noAdditionalIndentGlobal: environments: 0 commands: 1 optionalArguments: 0 mandatoryArguments: 0 ifElseFi: 0 items: 0 keyEqualsValuesBracesBrackets: 0 namedGroupingBracesBrackets: 0 UnNamedGroupingBracesBrackets: 0 specialBeginEnd: 0 afterHeading: 0 filecontents: 0 
Listing 254 indentRulesGlobal
 350 351 352 353 354 355 356 357 358 359 360 361 362 indentRulesGlobal: environments: 0 commands: 0 optionalArguments: 0 mandatoryArguments: 0 ifElseFi: 0 items: 0 keyEqualsValuesBracesBrackets: 0 namedGroupingBracesBrackets: 0 UnNamedGroupingBracesBrackets: 0 specialBeginEnd: 0 afterHeading: 0 filecontents: 0 

## 5.9. Commands and the strings between their arguments¶

The command code blocks will always look for optional (square bracketed) and mandatory (curly braced) arguments which can contain comments, line breaks and ‘beamer’ commands <.*?> between them. There are switches that can allow them to contain other strings, which we discuss next.

commandCodeBlocks:fields

The commandCodeBlocks field contains a few switches detailed in Listing 255.

Listing 255 commandCodeBlocks
 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 commandCodeBlocks: roundParenthesesAllowed: 1 stringsAllowedBetweenArguments: - amalgamate: 1 - 'node' - 'at' - 'to' - 'decoration' - '\+\+' - '\-\-' - '\#\#\d' commandNameSpecial: - amalgamate: 1 - '@ifnextchar\[' 
roundParenthesesAllowed:0|1

The need for this field was mostly motivated by commands found in code used to generate images in PSTricks and tikz; for example, let’s consider the code given in Listing 256.

Listing 256 pstricks1.tex
\defFunction[algebraic]{torus}(u,v)
{(2+cos(u))*cos(v+\Pi)}
{(2+cos(u))*sin(v+\Pi)}
{sin(u)}

Listing 257 pstricks1 default output
\defFunction[algebraic]{torus}(u,v)
{(2+cos(u))*cos(v+\Pi)}
{(2+cos(u))*sin(v+\Pi)}
{sin(u)}


Notice that the \defFunction command has an optional argument, followed by a mandatory argument, followed by a round-parenthesis argument, $$(u,v)$$.

By default, because roundParenthesesAllowed is set to $$1$$ in Listing 255, then latexindent.pl will allow round parenthesis between optional and mandatory arguments. In the case of the code in Listing 256, latexindent.pl finds all the arguments of defFunction, both before and after (u,v).

The default output from running latexindent.pl on Listing 256 actually leaves it unchanged (see Listing 257); note in particular, this is because of noAdditionalIndentGlobal as discussed on page page:command:noAddGlobal.

Upon using the YAML settings in Listing 259, and running the command

latexindent.pl pstricks1.tex -l noRoundParentheses.yaml


we obtain the output given in Listing 258.

Listing 258 pstricks1.tex using Listing 259
\defFunction[algebraic]{torus}(u,v)
{(2+cos(u))*cos(v+\Pi)}
{(2+cos(u))*sin(v+\Pi)}
{sin(u)}

Listing 259 noRoundParentheses.yaml
commandCodeBlocks:
roundParenthesesAllowed: 0


Notice the difference between Listing 257 and Listing 258; in particular, in Listing 258, because round parentheses are not allowed, latexindent.pl finds that the \defFunction command finishes at the first opening round parenthesis. As such, the remaining braced, mandatory, arguments are found to be UnNamedGroupingBracesBrackets (see Table 2) which, by default, assume indentation for their body, and hence the tabbed indentation in Listing 258.

Let’s explore this using the YAML given in Listing 261 and run the command

latexindent.pl pstricks1.tex -l defFunction.yaml


then the output is as in Listing 260.

Listing 260 pstricks1.tex using Listing 261
\defFunction[algebraic]{torus}(u,v)
{(2+cos(u))*cos(v+\Pi)}
{(2+cos(u))*sin(v+\Pi)}
{sin(u)}

Listing 261 defFunction.yaml
indentRules:
defFunction:
body: " "


Notice in Listing 260 that the body of the defFunction command i.e, the subsequent lines containing arguments after the command name, have received the single space of indentation specified by Listing 261.

stringsAllowedBetweenArguments:fields

tikz users may well specify code such as that given in Listing 262; processing this code using latexindent.pl gives the default output in Listing 263.

Listing 262 tikz-node1.tex
\draw[thin]
(c) to[in=110,out=-90]
++(0,-0.5cm)
node[below,align=left,scale=0.5]

Listing 263 tikz-node1 default output
\draw[thin]
(c) to[in=110,out=-90]
++(0,-0.5cm)
node[below,align=left,scale=0.5]


With reference to Listing 255, we see that the strings

to, node, ++

are all allowed to appear between arguments; importantly, you are encouraged to add further names to this field as necessary. This means that when latexindent.pl processes Listing 262, it consumes:

• the optional argument [thin]
• the round-bracketed argument (c) because roundParenthesesAllowed is $$1$$ by default
• the string to (specified in stringsAllowedBetweenArguments)
• the optional argument [in=110,out=-90]
• the string ++ (specified in stringsAllowedBetweenArguments)
• the round-bracketed argument (0,-0.5cm) because roundParenthesesAllowed is $$1$$ by default
• the string node (specified in stringsAllowedBetweenArguments)
• the optional argument [below,align=left,scale=0.5]

We can explore this further, for example using Listing 265 and running the command

latexindent.pl tikz-node1.tex -l draw.yaml


we receive the output given in Listing 264.

Listing 264 tikz-node1.tex using Listing 265
\draw[thin]
(c) to[in=110,out=-90]
++(0,-0.5cm)
node[below,align=left,scale=0.5]

Listing 265 draw.yaml
indentRules:
draw:
body: "  "


Notice that each line after the \draw command (its ‘body’) in Listing 264 has been given the appropriate two-spaces worth of indentation specified in Listing 265.

Let’s compare this with the output from using the YAML settings in Listing 267, and running the command

latexindent.pl tikz-node1.tex -l no-strings.yaml


given in Listing 266.

Listing 266 tikz-node1.tex using Listing 267
\draw[thin]
(c) to[in=110,out=-90]
++(0,-0.5cm)
node[below,align=left,scale=0.5]

Listing 267 no-strings.yaml
commandCodeBlocks:
stringsAllowedBetweenArguments: 0


In this case, latexindent.pl sees that:

• the \draw command finishes after the (c), as stringsAllowedBetweenArguments has been set to $$0$$ so there are no strings allowed between arguments;
• it finds a namedGroupingBracesBrackets called to (see Table 2) with argument [in=110,out=-90]
• it finds another namedGroupingBracesBrackets but this time called node with argument [below,align=left,scale=0.5]

Referencing Listing 255, , we see that the first field in the stringsAllowedBetweenArguments is amalgamate and is set to 1 by default. This is for users who wish to specify their settings in multiple YAML files. For example, by using the settings in either Listing 268 or:numref:lst:amalgamate-demo1 is equivalent to using the settings in Listing 270.

Listing 268 amalgamate-demo.yaml
commandCodeBlocks:
stringsAllowedBetweenArguments:
- 'more'
- 'strings'
- 'here'

Listing 269 amalgamate-demo1.yaml
commandCodeBlocks:
stringsAllowedBetweenArguments:
-
amalgamate: 1
- 'more'
- 'strings'
- 'here'

Listing 270 amalgamate-demo2.yaml
commandCodeBlocks:
stringsAllowedBetweenArguments:
-
amalgamate: 1
- 'node'
- 'at'
- 'to'
- 'decoration'
- '\+\+'
- '\-\-'
- 'more'
- 'strings'
- 'here'


We specify amalgamate to be set to 0 and in which case any settings loaded prior to those specified, including the default, will be overwritten. For example, using the settings in Listing 271 means that only the strings specified in that field will be used.

Listing 271 amalgamate-demo3.yaml
commandCodeBlocks:
stringsAllowedBetweenArguments:
-
amalgamate: 0
- 'further'
- 'settings'


It is important to note that the amalgamate field, if used, must be in the first field, and specified using the syntax given in Listing 269 and Listing 270 and Listing 271.

We may explore this feature further with the code in Listing 272, whose default output is given in Listing 273.

Listing 272 for-each.tex
\foreach \x/\y in {0/1,1/2}{
body of foreach
}

Listing 273 for-each default output
\foreach \x/\y in {0/1,1/2}{
body of foreach
}


Let’s compare this with the output from using the YAML settings in Listing 275, and running the command

latexindent.pl for-each.tex -l foreach.yaml


given in Listing 274.

Listing 274 for-each.tex using Listing 275
\foreach \x/\y in {0/1,1/2}{
body of foreach
}

Listing 275 foreach.yaml
commandCodeBlocks:
stringsAllowedBetweenArguments:
-
amalgamate: 0
- '\\x\/\\y'
- 'in'


You might like to compare the output given in Listing 273 and Listing 274. Note,in particular, in Listing 273 that the foreach command has not included any of the subsequent strings, and that the braces have been treated as a namedGroupingBracesBrackets. In Listing 274 the foreach command has been allowed to have \x/\y and in between arguments because of the settings given in Listing 275.

commandNameSpecial:fields

There are some special command names that do not fit within the names recognised by latexindent.pl, the first one of which is \@ifnextchar[. From the perspective of latexindent.pl, the whole of the text \@ifnextchar[ is a command, because it is immediately followed by sets of mandatory arguments. However, without the commandNameSpecial field, latexindent.pl would not be able to label it as such, because the [ is, necessarily, not matched by a closing ].

For example, consider the sample file in Listing 276, which has default output in Listing 277.

Listing 276 ifnextchar.tex
\parbox{
\@ifnextchar[{arg 1}{arg 2}
}

Listing 277 ifnextchar.tex default output
\parbox{
\@ifnextchar[{arg 1}{arg 2}
}


Notice that in Listing 277 the parbox command has been able to indent its body, because latexindent.pl has successfully found the command \@ifnextchar first; the pattern-matching of latexindent.pl starts from the inner most <thing> and works outwards, discussed in more detail on page page:phases.

For demonstration, we can compare this output with that given in Listing 278 in which the settings from Listing 279 have dictated that no special command names, including the \@ifnextchar[ command, should not be searched for specially; as such, the parbox command has been unable to indent its body successfully, because the \@ifnextchar[ command has not been found.

Listing 278 ifnextchar.tex using Listing 279
\parbox{
\@ifnextchar[{arg 1}{arg 2}
}

Listing 279 no-ifnextchar.yaml
commandCodeBlocks:
commandNameSpecial: 0


The amalgamate field can be used for commandNameSpecial, just as for stringsAllowedBetweenArguments. The same condition holds as stated previously, which we state again here:

Warning

It is important to note that the amalgamate field, if used, in either commandNameSpecial or stringsAllowedBetweenArguments must be in the first field, and specified using the syntax given in Listing 269 and Listing 270 and Listing 271.

“Data Dumper Demonstration.” n.d. Accessed June 18, 2021. https://stackoverflow.com/questions/7466825/how-do-you-sort-the-output-of-datadumper.
Data::Dumper Module.” n.d. Accessed June 18, 2021. https://perldoc.perl.org/Data::Dumper.
“Text::Tabs Perl Module.” n.d. Accessed July 6, 2017. http://search.cpan.org/~muir/Text-Tabs+Wrap-2013.0523/lib.old/Text/Tabs.pm.
Voßkuhle, Michel. 2013. “Remove Trailing White Space.” November 10, 2013. https://github.com/cmhughes/latexindent.pl/pull/12.
XuehaiPan. 2021. “Verbatim Block Upgrade.” October 3, 2021. https://github.com/cmhughes/latexindent.pl/pull/290.
 [1] Throughout this manual, listings shown with line numbers represent code taken directly from defaultSettings.yaml.
 [2] There is a slight difference in interface for this field when comparing Version 2.2 to Version 3.0; see Section 12.11 for details.
 [3] The command code blocks have quite a few subtleties, described in Section 5.9.
 [4] You may like to verify this by using the -tt option and checking indent.log!