4. The -m (modifylinebreaks) switch

All features described in this section will only be relevant if the -m switch is used.

modifylinebreaks:fields

As of Version 3.0, latexindent.pl has the -m switch, which permits latexindent.pl to modify line breaks, according to the specifications in the modifyLineBreaks field. The settings in this field will only be considered if the ``-m`` switch has been used. A snippet of the default settings of this field is shown in Listing 281.

Listing 281 modifyLineBreaks

modifyLineBreaks:
  preserveBlankLines: 1                 # 0/1
  condenseMultipleBlankLinesInto: 1     # 0/1

Having read the previous paragraph, it should sound reasonable that, if you call latexindent.pl using the -m switch, then you give it permission to modify line breaks in your file, but let’s be clear:

Warning

If you call latexindent.pl with the -m switch, then you are giving it permission to modify line breaks. By default, the only thing that will happen is that multiple blank lines will be condensed into one blank line; many other settings are possible, discussed next.

preserveBlankLines:0|1

This field is directly related to poly-switches, discussed in Section 4.3. By default, it is set to 1, which means that blank lines will be protected from removal; however, regardless of this setting, multiple blank lines can be condensed if condenseMultipleBlankLinesInto is greater than 0, discussed next.

condenseMultipleBlankLinesInto:positive integer

Assuming that this switch takes an integer value greater than 0, latexindent.pl will condense multiple blank lines into the number of blank lines illustrated by this switch.

Example 76

As an example, Listing 282 shows a sample file with blank lines; upon running

latexindent.pl myfile.tex -m -o=+-mod1

the output is shown in Listing 283; note that the multiple blank lines have been condensed into one blank line, and note also that we have used the -m switch!

Listing 282 mlb1.tex

before blank line

after blank line

after blank line

Listing 283 mlb1-mod1.tex

before blank line

after blank line

after blank line

4.1. Text Wrapping

The text wrapping routine has been over-hauled as of V3.16; I hope that the interface is simpler, and most importantly, the results are better.

The complete settings for this feature are given in Listing 284.

Listing 284 textWrapOptions

  textWrapOptions:
    columns: 0
    multipleSpacesToSingle: 1
    removeBlockLineBreaks: 1
    when: before                        # before/after
    comments:
      wrap: 0                           # 0/1
      inheritLeadingSpace: 0            # 0/1
    blocksFollow:
      headings: 1                       # 0/1
      commentOnPreviousLine: 1          # 0/1
      par: 1                            # 0/1
      blankLine: 1                      # 0/1
      verbatim: 1                       # 0/1
      other: \\\]|\\item(?:\h|\[)       # regex
    blocksBeginWith:
      A-Z: 1                            # 0/1
      a-z: 1                            # 0/1
      0-9: 0                            # 0/1
      other: 0                          # regex
    blocksEndBefore:
      commentOnOwnLine: 1               # 0/1
      verbatim: 1                       # 0/1
      other: \\begin\{|\\\[|\\end\{     # regex
    huge: overflow                      # forbid mid-word line breaks
    separator: ""

4.1.1. Text wrap: overview

An overview of how the text wrapping feature works:

the default value of columns is 0, which means that text wrapping will not happen by default;
it happens after verbatim blocks have been found;
it happens after the oneSentencePerLine routine (see Section 4.2);
it can happen before or after all of the other code blocks are found and does not operate on a per-code-block basis; when using before this means that, including indentation, you may receive a column width wider than that which you specify in columns, and in which case you probably wish to explore after in Section 4.1.7;
code blocks to be text wrapped will:
1. follow the fields specified in blocksFollow
2. begin with the fields specified in blocksBeginWith
3. end before the fields specified in blocksEndBefore
setting columns to a value $>0$ will text wrap blocks by first removing line breaks, and then wrapping according to the specified value of columns;
setting columns to $-1$ will only remove line breaks within the text wrap block;
by default, the text wrapping routine will remove line breaks within text blocks because removeBlockLineBreaks is set to 1; switch it to 0 if you wish to change this;
about trailing comments within text wrap blocks:
1. trailing comments that do not have leading space instruct the text wrap routine to connect the lines without space (see Listing 322);
2. multiple trailing comments will be connected at the end of the text wrap block (see Listing 326);
3. the number of spaces between the end of the text wrap block and the (possibly combined) trailing comments is determined by the spaces (if any) at the end of the text wrap block (see Listing 328);
trailing comments can receive text wrapping ; examples are shown in Section 4.1.8 and Section 4.2.9.

We demonstrate this feature using a series of examples.

4.1.2. Text wrap: simple examples

Example 77

Let’s use the sample text given in Listing 285.

Listing 285 textwrap1.tex

Here  is a line of text that will be wrapped by latexindent.pl.

Here is  a line of text that will be wrapped by latexindent.pl.

We will change the value of columns in Listing 287 and then run the command

latexindent.pl -m -l textwrap1.yaml textwrap1.tex

then we receive the output given in Listing 286.

Listing 286 textwrap1-mod1.tex

Here is a line of
text that will be
wrapped by
latexindent.pl.

Here is a line of
text that will be
wrapped by
latexindent.pl.

Listing 287 textwrap1.yaml

modifyLineBreaks:
    textWrapOptions:
        columns: 20

Example 78

If we set columns to $-1$ then latexindent.pl remove line breaks within the text wrap block, and will not perform text wrapping. We can use this to undo text wrapping.

Starting from the file in Listing 286 and using the settings in Listing 288

Listing 288 textwrap1A.yaml

modifyLineBreaks:
    textWrapOptions:
        columns: -1

and running

latexindent.pl -m -l textwrap1A.yaml textwrap1-mod1.tex

gives the output in Listing 289.

Listing 289 textwrap1-mod1A.tex

Here is a line of text that will be wrapped by latexindent.pl.

Here is a line of text that will be wrapped by latexindent.pl.

Example 79

By default, the text wrapping routine will convert multiple spaces into single spaces. You can change this behaviour by flicking the switch multipleSpacesToSingle which we have done in Listing 291

Using the settings in Listing 291 and running

latexindent.pl -m -l textwrap1B.yaml textwrap1-mod1.tex

gives the output in Listing 290.

Listing 290 textwrap1-mod1B.tex

Here  is a line of
text that will be
wrapped by
latexindent.pl.

Here is  a line of
text that will be
wrapped by
latexindent.pl.

Listing 291 textwrap1B.yaml

modifyLineBreaks:
    textWrapOptions:
        columns: 20
        multipleSpacesToSingle: 0

We note that in Listing 290 the multiple spaces have not been condensed into single spaces.

4.1.3. Text wrap: `blocksFollow` examples

We examine the blocksFollow field of Listing 284.

Example 80

Let’s use the sample text given in Listing 292.

Listing 292 tw-headings1.tex

\section{my heading}\label{mylabel1}
text to 
    be
 wrapped from the first section
\subsection{subheading}
text to 
    be
 wrapped from the first section

We note that Listing 292 contains the heading commands section and subsection. Upon running the command

latexindent.pl -m -l textwrap1.yaml tw-headings1.tex

then we receive the output given in Listing 293.

Listing 293 tw-headings1-mod1.tex

\section{my heading}\label{mylabel1}
text to be wrapped
from the first
section
\subsection{subheading}
text to be wrapped
from the first
section

We reference Listing 284 and also Listing 154:

in Listing 284 the headings field is set to 1, which instructs latexindent.pl to read the fields from Listing 154, regardless of the value of lookForThis or level;
the default is to assume that the heading command can, optionally, be followed by a label command.

If you find scenarios in which the default value of headings does not work, then you can explore the other field.

We can turn off headings as in Listing 295 and then run

latexindent.pl -m -l textwrap1.yaml,bf-no-headings.yaml tw-headings1.tex

gives the output in Listing 294, in which text wrapping has been instructed not to happen following headings.

Listing 294 tw-headings1-mod2.tex

\section{my heading}\label{mylabel1}
text to
be
wrapped from the first section
\subsection{subheading}
text to
be
wrapped from the first section

Listing 295 bf-no-headings.yaml

modifyLineBreaks:
    textWrapOptions:
        blocksFollow:
           headings: 0

Example 81

Let’s use the sample text given in Listing 296.

Listing 296 tw-comments1.tex

% trailing comment
text to 
    be
 wrapped following first comment
% another comment
text to 
    be
 wrapped following second comment

We note that Listing 296 contains trailing comments. Upon running the command

latexindent.pl -m -l textwrap1.yaml tw-comments1.tex

then we receive the output given in Listing 297.

Listing 297 tw-comments1-mod1.tex

% trailing comment
text to be wrapped
following first
comment
% another comment
text to be wrapped
following second
comment

With reference to Listing 284 the commentOnPreviousLine field is set to 1, which instructs latexindent.pl to find text wrap blocks after a comment on its own line.

We can turn off comments as in Listing 299 and then run

latexindent.pl -m -l textwrap1.yaml,bf-no-comments.yaml tw-comments1.tex

gives the output in Listing 298, in which text wrapping has been instructed not to happen following comments on their own line.

Listing 298 tw-comments1-mod2.tex

% trailing comment
text to
be
wrapped following first comment
% another comment
text to
be
wrapped following second comment

Listing 299 bf-no-comments.yaml

modifyLineBreaks:
    textWrapOptions:
        blocksFollow:
           commentOnPreviousLine: 0

Referencing Listing 284 the blocksFollow fields par, blankline, verbatim and filecontents fields operate in analogous ways to those demonstrated in the above.

The other field of the blocksFollow can either be 0 (turned off) or set as a regular expression. The default value is set to \\\]|\\item(?:\h|\[) which can be translated to backslash followed by a square bracket or backslash item followed by horizontal space or a square bracket, or in other words, end of display math or an item command.

Example 82

Let’s use the sample text given in Listing 300.

Listing 300 tw-disp-math1.tex

text to 
    be
 wrapped before display math
 \[ y = x\]
text to 
    be
 wrapped after display math

We note that Listing 300 contains display math. Upon running the command

latexindent.pl -m -l textwrap1.yaml tw-disp-math1.tex

then we receive the output given in Listing 301.

Listing 301 tw-disp-math1-mod1.tex

text to be wrapped
before display math
\[ y = x\]
text to be wrapped
after display math

With reference to Listing 284 the other field is set to \\\], which instructs latexindent.pl to find text wrap blocks after the end of display math.

We can turn off this switch as in Listing 303 and then run

latexindent.pl -m -l textwrap1.yaml,bf-no-disp-math.yaml tw-disp-math1.tex

gives the output in Listing 302, in which text wrapping has been instructed not to happen following display math.

Listing 302 tw-disp-math1-mod2.tex

text to be wrapped
before display math
\[ y = x\]
text to
be
wrapped after display math

Listing 303 bf-no-disp-math.yaml

modifyLineBreaks:
    textWrapOptions:
        blocksFollow:
           other: 0

Naturally, you should feel encouraged to customise this as you see fit.

The blocksFollow field deliberately does not default to allowing text wrapping to occur after begin environment statements. You are encouraged to customize the other field to accommodate the environments that you would like to text wrap individually, as in the next example.

Example 83

Let’s use the sample text given in Listing 304.

Listing 304 tw-bf-myenv1.tex

text to 
    be
 wrapped before myenv environment
 \begin{myenv}
text to 
    be
 wrapped within myenv environment
 \end{myenv}
text to 
    be
 wrapped after myenv environment

We note that Listing 304 contains myenv environment. Upon running the command

latexindent.pl -m -l textwrap1.yaml tw-bf-myenv1.tex

then we receive the output given in Listing 305.

Listing 305 tw-bf-myenv1-mod1.tex

text to be wrapped
before myenv
environment
\begin{myenv}
	text to
	be
	wrapped within myenv environment
\end{myenv}
text to
be
wrapped after myenv environment

We note that we have not received much text wrapping. We can turn do better by employing Listing 307 and then run

latexindent.pl -m -l textwrap1.yaml,tw-bf-myenv.yaml tw-bf-myenv1.tex

which gives the output in Listing 306, in which text wrapping has been implemented across the file.

Listing 306 tw-bf-myenv1-mod2.tex

text to be wrapped
before myenv
environment
\begin{myenv}
	text to be wrapped
	within myenv
	environment
\end{myenv}
text to be wrapped
after myenv
environment

Listing 307 tw-bf-myenv.yaml

modifyLineBreaks:
    textWrapOptions:
        blocksFollow:
           other: |-
             (?x)
                \\\]
                |
                \\item(?:\h|\[)
                |
                \\begin\{myenv\} # <--- new bit
                |                # <--- new bit
                \\end\{myenv\}   # <--- new bit

4.1.4. Text wrap: `blocksBeginWith` examples

We examine the blocksBeginWith field of Listing 284 with a series of examples.

Example 84

By default, text wrap blocks can begin with the characters a-z and A-Z.

If we start with the file given in Listing 308

Listing 308 tw-0-9.tex

123 text to 
    be
 wrapped before display math
 \[ y = x\]
456 text to 
    be
 wrapped after display math

and run the command

latexindent.pl -m -l textwrap1.yaml tw-0-9.tex

then we receive the output given in Listing 309 in which text wrapping has not occurred.

Listing 309 tw-0-9-mod1.tex

123 text to
be
wrapped before display math
\[ y = x\]
456 text to
be
wrapped after display math

We can allow paragraphs to begin with 0-9 characters by using the settings in Listing 311 and running

latexindent.pl -m -l textwrap1.yaml,bb-0-9-yaml tw-0-9.tex

gives the output in Listing 310, in which text wrapping has happened.

Listing 310 tw-0-9-mod2.tex

123 text to be
wrapped before
display math
\[ y = x\]
456 text to be
wrapped after
display math

Listing 311 bb-0-9.yaml.yaml

modifyLineBreaks:
    textWrapOptions:
        blocksBeginWith:
           0-9: 1

Example 85

Let’s now use the file given in Listing 312

Listing 312 tw-bb-announce1.tex

% trailing comment
\announce{announce text}
    and text 
    to be
 wrapped before 
  goes here

and run the command

latexindent.pl -m -l textwrap1.yaml tw-bb-announce1.tex

then we receive the output given in Listing 313 in which text wrapping has not occurred.

Listing 313 tw-bb-announce1-mod1.tex

% trailing comment
\announce{announce text}
and text
to be
wrapped before
goes here

We can allow \announce to be at the beginning of paragraphs by using the settings in Listing 315 and running

latexindent.pl -m -l textwrap1.yaml,tw-bb-announce.yaml tw-bb-announce1.tex

gives the output in Listing 314, in which text wrapping has happened.

Listing 314 tw-bb-announce1-mod2.tex

% trailing comment
\announce{announce
	text} and text to
be wrapped before
goes here

Listing 315 tw-bb-announce.yaml

modifyLineBreaks:
    textWrapOptions:
        blocksBeginWith:
           other: '\\announce'

4.1.5. Text wrap: `blocksEndBefore` examples

We examine the blocksEndBefore field of Listing 284 with a series of examples.

Example 86

Let’s use the sample text given in Listing 316.

Listing 316 tw-be-equation.tex

before 
equation
text
\begin{align}
  1 & 2 \\
  3 & 4
\end{align}
after 
equation
text

We note that Listing 316 contains an environment. Upon running the command

latexindent.pl -m -l textwrap1A.yaml tw-be-equation.tex

then we receive the output given in Listing 317.

Listing 317 tw-be-equation-mod1.tex

before equation text
\begin{align}
	1 & 2 \\
	3 & 4
\end{align}
after
equation
text

With reference to Listing 284 the other field is set to \\begin\{|\\\[|\\end\{, which instructs latexindent.pl to stop text wrap blocks before begin statements, display math, and end statements.

We can turn off this switch as in Listing 318 and then run

latexindent.pl -m -l textwrap1A.yaml,tw-be-equation.yaml tw-be-equation.tex

gives the output in Listing 319, in which text wrapping has been instructed not to stop at these statements.

Listing 318 tw-be-equation.yaml

modifyLineBreaks:
    textWrapOptions:
        blocksEndBefore:
           other: 0

Listing 319 tw-be-equation-mod2.tex

before equation text \begin{align} 1 & 2 \\ 3 & 4 \end{align} after equation text

Naturally, you should feel encouraged to customise this as you see fit.

4.1.6. Text wrap: trailing comments and spaces

We explore the behaviour of the text wrap routine in relation to trailing comments using the following examples.

Example 87

The file in Listing 320 contains a trailing comment which does have a space infront of it.

Running the command

latexindent.pl -m tw-tc1.tex -l textwrap1A.yaml -o=+-mod1

gives the output given in Listing 321.

Listing 320 tw-tc1.tex

foo %
bar

Listing 321 tw-tc1-mod1.tex

foo bar%

Example 88

The file in Listing 322 contains a trailing comment which does not have a space infront of it.

Running the command

latexindent.pl -m tw-tc2.tex -l textwrap1A.yaml -o=+-mod1

gives the output in Listing 323.

Listing 322 tw-tc2.tex

foo%
bar

Listing 323 tw-tc2-mod1.tex

foobar%

We note that, because there is not a space before the trailing comment, that the lines have been joined without a space.

Example 89

The file in Listing 324 contains multiple trailing comments.

Running the command

latexindent.pl -m tw-tc3.tex -l textwrap1A.yaml -o=+-mod1

gives the output in Listing 325.

Listing 324 tw-tc3.tex

foo %1
bar%2
three

Listing 325 tw-tc3-mod1.tex

foo barthree%1%2

Example 90

The file in Listing 326 contains multiple trailing comments.

Running the command

latexindent.pl -m tw-tc4.tex -l textwrap1A.yaml -o=+-mod1

gives the output in Listing 327.

Listing 326 tw-tc4.tex

foo %1
bar%2
three%3

Listing 327 tw-tc4-mod1.tex

foo barthree%1%2%3

Example 91

The file in Listing 328 contains multiple trailing comments.

Running the command

latexindent.pl -m tw-tc5.tex -l textwrap1A.yaml -o=+-mod1

gives the output in Listing 329.

Listing 328 tw-tc5.tex

foo%1
bar%2
three %3

Listing 329 tw-tc5-mod1.tex

foobarthree %1%2%3

The space at the end of the text block has been preserved.

Example 92

The file in Listing 330 contains multiple trailing comments.

Running the command

latexindent.pl -m tw-tc6.tex -l textwrap1A.yaml -o=+-mod1

gives the output in Listing 331.

Listing 330 tw-tc6.tex

foo%1
bar 

Listing 331 tw-tc6-mod1.tex

foobar %1

The space at the end of the text block has been preserved.

4.1.7. Text wrap: when before/after

The text wrapping routine operates, by default, before the code blocks have been found, but this can be changed to after:

before means it is likely that the columns of wrapped text may exceed the value specified in columns;
after means it columns of wrapped text should not exceed the value specified in columns.

We demonstrate this in the following examples. See also Section 4.2.8.

Example 93

Let’s begin with the file in Listing 332.

Listing 332 textwrap8.tex

This paragraph
has line breaks throughout its paragraph;
we would like to combine
the textwrapping
and paragraph removal routine.
\begin{myenv}
This paragraph
has line breaks throughout its paragraph;
we would like to combine
the textwrapping
and paragraph removal routine.
\end{myenv}

Using the settings given in Listing 334 and running the command

latexindent.pl textwrap8.tex -o=+-mod1.tex -l=tw-before1.yaml -m

gives the output given in Listing 333.

Listing 333 textwrap8-mod1.tex

This paragraph has line breaks
throughout its paragraph; we would
like to combine the textwrapping
and paragraph removal routine.
\begin{myenv}
  This paragraph has line breaks
  throughout its paragraph; we would
  like to combine the textwrapping
  and paragraph removal routine.
\end{myenv}
----|----|----|----|----|----|----|----|
   5   10   15   20   25   30   35   40

Listing 334 tw-before1.yaml

defaultIndent: '  '

modifyLineBreaks:
    textWrapOptions:
        columns: 35
        when: before  # <!-------
        blocksFollow:
          other: \\begin\{myenv\}

We note that, in Listing 333, that the wrapped text has exceeded the specified value of columns (35) given in Listing 334. We can affect this by changing when; we explore this next.

Example 94

We continue working with Listing 332.

Using the settings given in Listing 336 and running the command

latexindent.pl textwrap8.tex -o=+-mod2.tex -l=tw-after1.yaml -m

gives the output given in Listing 335.

Listing 335 textwrap8-mod2.tex

This paragraph has line breaks
throughout its paragraph; we would
like to combine the textwrapping
and paragraph removal routine.
\begin{myenv}
  This paragraph has line breaks
  throughout its paragraph; we
  would like to combine the
  textwrapping and paragraph
  removal routine.
\end{myenv}
----|----|----|----|----|----|----|----|
   5   10   15   20   25   30   35   40

Listing 336 tw-after1.yaml

defaultIndent: '  '

modifyLineBreaks:
    textWrapOptions:
        columns: 35
        when: after   # <!-------
        blocksFollow:
          other: \\begin\{myenv\}

We note that, in Listing 335, that the wrapped text has obeyed the specified value of columns (35) given in Listing 336.

4.1.8. Text wrap: wrapping comments

You can instruct latexindent.pl to apply text wrapping to comments ; we demonstrate this with examples, see also Section 4.2.9.

Example 95

We use the file in Listing 337 which contains a trailing comment block.

Listing 337 textwrap9.tex

My first sentence
% first comment
%   second
%third comment
%     fourth

Using the settings given in Listing 339 and running the command

latexindent.pl textwrap9.tex -o=+-mod1.tex -l=wrap-comments1.yaml -m

gives the output given in Listing 338.

Listing 338 textwrap9-mod1.tex

My first sentence
% first comment second third
% comment fourth
----|----|----|----|----|----|----|----|
   5   10   15   20   25   30   35   40

Listing 339 wrap-comments1.yaml

modifyLineBreaks:
  textWrapOptions:
    columns: 35
    comments: 
      wrap: 1  #<!-------

We note that, in Listing 338, that the comments have been combined and wrapped because of the annotated line specified in Listing 339.

Example 96

We use the file in Listing 340 which contains a trailing comment block.

Listing 340 textwrap10.tex

My first sentence
%    first comment
%   second
%third comment
%     fourth

Using the settings given in Listing 342 and running the command

latexindent.pl textwrap10.tex -o=+-mod1.tex -l=wrap-comments1.yaml -m

gives the output given in Listing 341.

Listing 341 textwrap10-mod1.tex

My first sentence
% first comment second third
% comment fourth
----|----|----|----|----|----|----|----|
   5   10   15   20   25   30   35   40

Listing 342 wrap-comments1.yaml

modifyLineBreaks:
  textWrapOptions:
    columns: 35
    comments: 
      wrap: 1  #<!-------

We note that, in Listing 341, that the comments have been combined and wrapped because of the annotated line specified in Listing 342, and that the space from the leading comment has not been inherited; we will explore this further in the next example.

Example 97

We continue to use the file in Listing 340.

Using the settings given in Listing 344 and running the command

latexindent.pl textwrap10.tex -o=+-mod2.tex -l=wrap-comments2.yaml -m

gives the output given in Listing 343.

Listing 343 textwrap10-mod2.tex

My first sentence
%    first comment second third
%    comment fourth
----|----|----|----|----|----|----|----|
   5   10   15   20   25   30   35   40

Listing 344 wrap-comments2.yaml

modifyLineBreaks:
  textWrapOptions:
    columns: 35
    comments: 
      wrap: 1                #<!-------
      inheritLeadingSpace: 1 #<!-------

We note that, in Listing 343, that the comments have been combined and wrapped and that the leading space has been inherited because of the annotated lines specified in Listing 344.

4.1.9. Text wrap: huge, tabstop and separator

The default value of huge is overflow, which means that words will not be broken by the text wrapping routine, implemented by the Text::Wrap (“Text::Wrap Perl Module” n.d.). There are options to change the huge option for the Text::Wrap module to either wrap or die. Before modifying the value of huge, please bear in mind the following warning:

Warning

Changing the value of huge to anything other than overflow will slow down latexindent.pl significantly when the -m switch is active.

Furthermore, changing huge means that you may have some words or commands(!) split across lines in your .tex file, which may affect your output. I do not recommend changing this field.

Example 98

For example, using the settings in Listing 346 and Listing 348 and running the commands

     latexindent.pl -m textwrap4.tex -o=+-mod2A -l textwrap2A.yaml
     latexindent.pl -m textwrap4.tex -o=+-mod2B -l textwrap2B.yaml

gives the respective output in Listing 345 and Listing 347.

Listing 345 textwrap4-mod2A.tex

He
re
is
a
li
ne
of
te
xt
.

Listing 346 textwrap2A.yaml

modifyLineBreaks:
  textWrapOptions:
    columns: 3
    huge: wrap

Listing 347 textwrap4-mod2B.tex

Here
is
a
line
of
text.

Listing 348 textwrap2B.yaml

modifyLineBreaks:
  textWrapOptions:
    columns: 3

You can also specify the tabstop field as an integer value, which is passed to the text wrap module; see (“Text::Wrap Perl Module” n.d.) for details.

Example 99

Starting with the code in Listing 349 with settings in Listing 350, and running the command

     latexindent.pl -m textwrap-ts.tex -o=+-mod1 -l tabstop.yaml

gives the code given in Listing 351.

Listing 349 textwrap-ts.tex

x       y

Listing 350 tabstop.yaml

modifyLineBreaks:
    textWrapOptions:
        columns: 80
        tabstop: 9
        multipleSpacesToSingle: 0

Listing 351 textwrap-ts-mod1.tex

x       y

You can specify separator, break and unexpand options in your settings in analogous ways to those demonstrated in Listing 348 and Listing 350, and they will be passed to the Text::Wrap module. I have not found a useful reason to do this; see (“Text::Wrap Perl Module” n.d.) for more details.

4.2. oneSentencePerLine: modifying line breaks for sentences

You can instruct latexindent.pl to format your file so that it puts one sentence per line. Thank you to (mlep 2017) for helping to shape and test this feature. The behaviour of this part of the script is controlled by the switches detailed in Listing 352, all of which we discuss next.

Listing 352 oneSentencePerLine

  oneSentencePerLine:
    manipulateSentences: 0              # 0/1
    removeSentenceLineBreaks: 1         # 0/1
    multipleSpacesToSingle: 1           # 0/1
    textWrapSentences: 0                # 1 disables main textWrap
    sentenceIndent: ""
    sentencesFollow:
      par: 1                            # 0/1
      blankLine: 1                      # 0/1
      fullStop: 1                       # 0/1
      exclamationMark: 1                # 0/1
      questionMark: 1                   # 0/1
      rightBrace: 1                     # 0/1
      commentOnPreviousLine: 1          # 0/1
      other: 0                          # regex
    sentencesBeginWith:
      A-Z: 1                            # 0/1
      a-z: 0                            # 0/1
      other: 0                          # regex
    sentencesEndWith:
      basicFullStop: 0                  # 0/1
      betterFullStop: 1                 # 0/1
      exclamationMark: 1                # 0/1
      questionMark: 1                   # 0/1
      other: 0                          # regex
    sentencesDoNOTcontain:
      other: \\begin                    # regex

4.2.1. oneSentencePerLine: overview

An overview of how the oneSentencePerLine routine feature works:

the default value of manipulateSentences is 0, which means that oneSentencePerLine will not happen by default;
it happens after verbatim blocks have been found;
it happens before the text wrapping routine (see Section 4.1);
it happens before the main code blocks have been found;
sentences to be found:
1. follow the fields specified in sentencesFollow
2. begin with the fields specified in sentencesBeginWith
3. end with the fields specified in sentencesEndWith
by default, the oneSentencePerLine routine will remove line breaks within sentences because removeSentenceLineBreaks is set to 1; switch it to 0 if you wish to change this;
sentences can be text wrapped according to textWrapSentences, and will be done either before or after the main indentation routine (see Section 4.2.8);
about trailing comments within text wrap blocks:
1. multiple trailing comments will be connected at the end of the sentence;
2. the number of spaces between the end of the sentence and the (possibly combined) trailing comments is determined by the spaces (if any) at the end of the sentence.

We demonstrate this feature using a series of examples. .. describe:: manipulateSentences:0|1

This is a binary switch that details if latexindent.pl should perform the sentence manipulation routine; it is off (set to 0) by default, and you will need to turn it on (by setting it to 1) if you want the script to modify line breaks surrounding and within sentences.

removeSentenceLineBreaks:0|1

When operating upon sentences latexindent.pl will, by default, remove internal line breaks as removeSentenceLineBreaks is set to 1. Setting this switch to 0 instructs latexindent.pl not to do so.

Example 100

For example, consider multiple-sentences.tex shown in Listing 353.

Listing 353 multiple-sentences.tex

This is the first
sentence. This is the; second, sentence. This is the
third sentence.

This is the fourth
sentence! This is the fifth sentence? This is the
sixth sentence.

If we use the YAML files in Listing 355 and Listing 357, and run the commands

latexindent.pl multiple-sentences -m -l=manipulate-sentences.yaml
latexindent.pl multiple-sentences -m -l=keep-sen-line-breaks.yaml

then we obtain the respective output given in Listing 354 and Listing 356.

Listing 354 multiple-sentences.tex using Listing 355

This is the first sentence.
This is the; second, sentence.
This is the third sentence.

This is the fourth sentence!
This is the fifth sentence?
This is the sixth sentence.

Listing 355 manipulate-sentences.yaml

modifyLineBreaks:
    oneSentencePerLine:
        manipulateSentences: 1

Listing 356 multiple-sentences.tex using Listing 357

This is the first
sentence.
This is the; second, sentence.
This is the
third sentence.

This is the fourth
sentence!
This is the fifth sentence?
This is the
sixth sentence.

Listing 357 keep-sen-line-breaks.yaml

modifyLineBreaks:
    oneSentencePerLine:
        manipulateSentences: 1
        removeSentenceLineBreaks: 0

Notice, in particular, that the ‘internal’ sentence line breaks in Listing 353 have been removed in Listing 354, but have not been removed in Listing 356.

multipleSpacesToSingle:0|1

By default, the one-sentence-per-line routine will convert multiple spaces into single spaces. You can change this behaviour by changing the switch multipleSpacesToSingle to a value of 0.

The remainder of the settings displayed in Listing 352 instruct latexindent.pl on how to define a sentence. From the perspective of latexindent.pl a sentence must:

follow a certain character or set of characters (see Listing 358); by default, this is either \par, a blank line, a full stop/period (.), exclamation mark (!), question mark (?) right brace (}) or a comment on the previous line;
begin with a character type (see Listing 359); by default, this is only capital letters;
end with a character (see Listing 360); by default, these are full stop/period (.), exclamation mark (!) and question mark (?).

In each case, you can specify the other field to include any pattern that you would like; you can specify anything in this field using the language of regular expressions.

Listing 358 sentencesFollow

    sentencesFollow:
      par: 1                            # 0/1
      blankLine: 1                      # 0/1
      fullStop: 1                       # 0/1
      exclamationMark: 1                # 0/1
      questionMark: 1                   # 0/1
      rightBrace: 1                     # 0/1
      commentOnPreviousLine: 1          # 0/1
      other: 0                          # regex

Listing 359 sentencesBeginWith

    sentencesBeginWith:
      A-Z: 1                            # 0/1
      a-z: 0                            # 0/1
      other: 0                          # regex

Listing 360 sentencesEndWith

    sentencesEndWith:
      basicFullStop: 0                  # 0/1
      betterFullStop: 1                 # 0/1
      exclamationMark: 1                # 0/1
      questionMark: 1                   # 0/1
      other: 0                          # regex

4.2.2. oneSentencePerLine: sentencesFollow

Let’s explore a few of the switches in sentencesFollow.

Example 101

We start with Listing 353, and use the YAML settings given in Listing 362. Using the command

latexindent.pl multiple-sentences -m -l=sentences-follow1.yaml

we obtain the output given in Listing 361.

Listing 361 multiple-sentences.tex using Listing 362

This is the first sentence.
This is the; second, sentence.
This is the third sentence.

This is the fourth
sentence!
This is the fifth sentence?
This is the sixth sentence.

Listing 362 sentences-follow1.yaml

modifyLineBreaks:
    oneSentencePerLine:
        manipulateSentences: 1
        sentencesFollow:
            blankLine: 0

Notice that, because blankLine is set to 0, latexindent.pl will not seek sentences following a blank line, and so the fourth sentence has not been accounted for.

Example 102

We can explore the other field in Listing 358 with the .tex file detailed in Listing 363.

Listing 363 multiple-sentences1.tex

(Some sentences stand alone in brackets.) This is the first
sentence. This is the; second, sentence. This is the
third sentence. 

Upon running the following commands

latexindent.pl multiple-sentences1 -m -l=manipulate-sentences.yaml
latexindent.pl multiple-sentences1 -m -l=manipulate-sentences.yaml,sentences-follow2.yaml

then we obtain the respective output given in Listing 364 and Listing 365.

Listing 364 multiple-sentences1.tex using Listing 355

(Some sentences stand alone in brackets.) This is the first
sentence.
This is the; second, sentence.
This is the third sentence.

Listing 365 multiple-sentences1.tex using Listing 366

(Some sentences stand alone in brackets.)
This is the first sentence.
This is the; second, sentence.
This is the third sentence.

Listing 366 sentences-follow2.yaml

modifyLineBreaks:
    oneSentencePerLine:
        manipulateSentences: 1
        sentencesFollow:
           other: "\)"

Notice that in Listing 364 the first sentence after the ) has not been accounted for, but that following the inclusion of Listing 366, the output given in Listing 365 demonstrates that the sentence has been accounted for correctly.

4.2.3. oneSentencePerLine: sentencesBeginWith

By default, latexindent.pl will only assume that sentences begin with the upper case letters A-Z; you can instruct the script to define sentences to begin with lower case letters (see Listing 359), and we can use the other field to define sentences to begin with other characters.

Example 103

We use the file in Listing 367.

Listing 367 multiple-sentences2.tex

This is the first
sentence. 

$a$ can 
represent a 
number. 7 is
at the beginning of this sentence.

Upon running the following commands

latexindent.pl multiple-sentences2 -m -l=manipulate-sentences.yaml
latexindent.pl multiple-sentences2 -m -l=manipulate-sentences.yaml,sentences-begin1.yaml

then we obtain the respective output given in Listing 368 and Listing 369.

Listing 368 multiple-sentences2.tex using Listing 355

This is the first sentence.

$a$ can
represent a
number. 7 is
at the beginning of this sentence.

Listing 369 multiple-sentences2.tex using Listing 370

This is the first sentence.

$a$ can represent a number.
7 is at the beginning of this sentence.

Listing 370 sentences-begin1.yaml

modifyLineBreaks:
    oneSentencePerLine:
        manipulateSentences: 1
        sentencesBeginWith:
            other: "\$|[0-9]"

Notice that in Listing 368, the first sentence has been accounted for but that the subsequent sentences have not. In Listing 369, all of the sentences have been accounted for, because the other field in Listing 370 has defined sentences to begin with either $ or any numeric digit, 0 to 9.

4.2.4. oneSentencePerLine: sentencesEndWith

Example 104

Let’s return to Listing 353; we have already seen the default way in which latexindent.pl will operate on the sentences in this file in Listing 354. We can populate the other field with any character that we wish; for example, using the YAML specified in Listing 372 and the command

latexindent.pl multiple-sentences -m -l=sentences-end1.yaml
latexindent.pl multiple-sentences -m -l=sentences-end2.yaml

then we obtain the output in Listing 371.

Listing 371 multiple-sentences.tex using Listing 372

This is the first sentence.
This is the;
second, sentence.
This is the third sentence.

This is the fourth sentence!
This is the fifth sentence?
This is the sixth sentence.

Listing 372 sentences-end1.yaml

modifyLineBreaks:
    oneSentencePerLine:
        manipulateSentences: 1
        sentencesEndWith:
          other: "\:|\;|\,"

Listing 373 multiple-sentences.tex using Listing 374

This is the first sentence.
This is the;
second,
sentence.
This is the third sentence.

This is the fourth sentence!
This is the fifth sentence?
This is the sixth sentence.

Listing 374 sentences-end2.yaml

modifyLineBreaks:
    oneSentencePerLine:
        manipulateSentences: 1
        sentencesEndWith:
          other: "\:|\;|\,"
        sentencesBeginWith:
          a-z: 1

There is a subtle difference between the output in Listing 371 and Listing 373; in particular, in Listing 371 the word sentence has not been defined as a sentence, because we have not instructed latexindent.pl to begin sentences with lower case letters. We have changed this by using the settings in Listing 374, and the associated output in Listing 373 reflects this.

Referencing Listing 360, you’ll notice that there is a field called basicFullStop, which is set to 0, and that the betterFullStop is set to 1 by default.

Example 105

Let’s consider the file shown in Listing 375.

Listing 375 url.tex

This sentence, \url{tex.stackexchange.com/} finishes here. Second sentence.

Upon running the following commands

latexindent.pl url -m -l=manipulate-sentences.yaml

we obtain the output given in Listing 376.

Listing 376 url.tex using Listing 355

This sentence, \url{tex.stackexchange.com/} finishes here.
Second sentence.

Notice that the full stop within the url has been interpreted correctly. This is because, within the betterFullStop, full stops at the end of sentences have the following properties:

they are ignored within e.g. and i.e.;
they can not be immediately followed by a lower case or upper case letter;
they can not be immediately followed by a hyphen, comma, or number.

If you find that the betterFullStop does not work for your purposes, then you can switch it off by setting it to 0, and you can experiment with the other field. You can also seek to customise the betterFullStop routine by using the fine tuning, detailed in Listing 559.

The basicFullStop routine should probably be avoided in most situations, as it does not accommodate the specifications above.

Example 106

For example, using the following command

latexindent.pl url -m -l=alt-full-stop1.yaml

and the YAML in Listing 378 gives the output in Listing 377.

Listing 377 url.tex using Listing 378

This sentence, \url{tex.
	stackexchange.com/} finishes here.
Second sentence.

Listing 378 alt-full-stop1.yaml

modifyLineBreaks:
    oneSentencePerLine:
        manipulateSentences: 1
        sentencesEndWith:
            basicFullStop: 1
            betterFullStop: 0

Notice that the full stop within the URL has not been accommodated correctly because of the non-default settings in Listing 378.

4.2.5. oneSentencePerLine: sentencesDoNOTcontain

You can specify patterns that sentences do not contain using the field in Listing 379.

Listing 379 sentencesDoNOTcontain

    sentencesDoNOTcontain:
      other: \\begin                    # regex

If sentences run across environments then, by default, they will not be considered a sentence by latexindent.pl.

Example 107

For example, if we use the .tex file in Listing 380

Listing 380 multiple-sentences4.tex

This sentence 
\begin{itemize}
  \item continues
\end{itemize}
across itemize 
and finishes here.

and run the command

latexindent.pl multiple-sentences4 -m -l=manipulate-sentences.yaml

then the output is unchanged, because the default value of sentencesDoNOTcontain says, sentences do NOT contain

This means that, by default, latexindent.pl does not consider the file in Listing 380 to have a sentence. \\begin

Example 108

We can customise the sentencesDoNOTcontain field with anything that we do not want sentences to contain.

We begin with the file in Listing 381.

Listing 381 sentence-dnc1.tex

This should not be a sentence \cmh{?} and should not change.
But this
one should.

Upon running the following commands

latexindent.pl sentence-dnc1.tex -m -l=dnc1.yaml

then we obtain the output given in Listing 382.

Listing 382 sentence-dnc1-mod1.tex

This should not be a sentence \cmh{?} and should not change.
But this one should.

Listing 383 dnc1.yaml

modifyLineBreaks:
    oneSentencePerLine:
        manipulateSentences: 1
        sentencesDoNOTcontain:
            other: |-
              (?x)
              \\begin
              |
              \\cmh

The settings in Listing 383 say that sentences do not contain \begin and that they do not contain \cmh

Example 109

We can implement case insensitivity for the sentencesDoNOTcontain field.

We begin with the file in Listing 384.

Listing 384 sentence-dnc2.tex

This should not be a sentence \cmh{?} and should not change.
This should not be a sentence \CMH{?} and should not change.
But this
one should.

Upon running the following commands

latexindent.pl sentence-dnc2.tex -m -l=dnc2.yaml

then we obtain the output given in Listing 385.

Listing 385 sentence-dnc2-mod2.tex

This should not be a sentence \cmh{?} and should not change.
This should not be a sentence \CMH{?} and should not change.
But this one should.

Listing 386 dnc2.yaml

modifyLineBreaks:
    oneSentencePerLine:
        manipulateSentences: 1
        sentencesDoNOTcontain:
            other: |-
              (?xi)    #<!----
              \\begin
              |
              \\cmh

The settings in Listing 386 say that sentences do not contain \begin and that they do not contain case insensitive versions of \cmh

Example 110

We can turn off sentenceDoNOTcontain by setting it to 0 as in Listing 387.

Listing 387 dnc-off.yaml

modifyLineBreaks:
    oneSentencePerLine:
        manipulateSentences: 1
        sentencesDoNOTcontain: 0

The settings in Listing 387 mean that sentences can contain any character.

4.2.6. Features of the oneSentencePerLine routine

The sentence manipulation routine takes place after verbatim

environments, preamble and trailing comments have been accounted for; this means that any characters within these types of code blocks will not be part of the sentence manipulation routine.

Example 111

For example, if we begin with the .tex file in Listing 388, and run the command

latexindent.pl multiple-sentences3 -m -l=manipulate-sentences.yaml

then we obtain the output in Listing 389.

Listing 388 multiple-sentences3.tex

The first sentence continues after the verbatim
\begin{verbatim}
  there are sentences within this. These 
  will not be operated
  upon by latexindent.pl. 
\end{verbatim}
and finishes here. Second sentence % a commented full stop.
contains trailing comments,
which are ignored.

Listing 389 multiple-sentences3.tex using Listing 355

The first sentence continues after the verbatim \begin{verbatim}
  there are sentences within this. These 
  will not be operated
  upon by latexindent.pl. 
\end{verbatim} and finishes here.
Second sentence contains trailing comments, which are ignored.
% a commented full stop.

4.2.7. oneSentencePerLine: text wrapping and indenting sentences

The oneSentencePerLine can be instructed to perform text wrapping and indentation upon sentences.

Example 112

Let’s use the code in Listing 390.

Listing 390 multiple-sentences5.tex

A distincao entre conteudo \emph{real} e conteudo \emph{intencional} esta
relacionada, ainda, a distincao entre o conceito husserliano de
\emph{experiencia} e o uso popular desse termo. No sentido comum,
o \term{experimentado} e um complexo de eventos exteriores,
e o \term{experimentar} consiste em percepcoes (alem de julgamentos e outros
atos) nas quais tais eventos aparecem como objetos, e objetos frequentemente
to the end.

Referencing Listing 392, and running the following command

latexindent.pl multiple-sentences5 -m -l=sentence-wrap1.yaml

we receive the output given in Listing 391.

Listing 391 multiple-sentences5.tex using Listing 392

A distincao entre conteudo \emph{real} e conteudo
  \emph{intencional} esta relacionada, ainda, a
  distincao entre o conceito husserliano de
  \emph{experiencia} e o uso popular desse termo.
No sentido comum, o \term{experimentado} e um
  complexo de eventos exteriores, e o
  \term{experimentar} consiste em percepcoes (alem
  de julgamentos e outros atos) nas quais tais
  eventos aparecem como objetos, e objetos
  frequentemente to the end.

Listing 392 sentence-wrap1.yaml

modifyLineBreaks:
    oneSentencePerLine:
        manipulateSentences: 1     
        removeSentenceLineBreaks: 1
        textWrapSentences: 1
        sentenceIndent: "  "
    textWrapOptions:
        columns: 50

If you specify textWrapSentences as 1, but do not specify a value for columns then the text wrapping will not operate on sentences, and you will see a warning in indent.log.

Example 113

The indentation of sentences requires that sentences are stored as code blocks. This means that you may need to tweak Listing 360. Let’s explore this in relation to Listing 393.

Listing 393 multiple-sentences6.tex

Consider the following:
\begin{itemize}
        \item firstly.
        \item secondly.
\end{itemize}

By default, latexindent.pl will find the full-stop within the first item, which means that, upon running the following commands

latexindent.pl multiple-sentences6 -m -l=sentence-wrap1.yaml
latexindent.pl multiple-sentences6 -m -l=sentence-wrap1.yaml -y="modifyLineBreaks:oneSentencePerLine:sentenceIndent:''"

we receive the respective output in Listing 394 and Listing 395.

Listing 394 multiple-sentences6-mod1.tex using Listing 392

Consider the following:
\begin{itemize}
	\item firstly.
	\item secondly.
\end{itemize}

Listing 395 multiple-sentences6-mod2.tex using Listing 392 and no sentence indentation

Consider the following:
\begin{itemize}
	\item firstly.
	\item secondly.
\end{itemize}

We note that Listing 394 the itemize code block has not been indented appropriately. This is because the oneSentencePerLine has been instructed to store sentences (because Listing 392); each sentence is then searched for code blocks.

Example 114

We can tweak the settings in Listing 360 to ensure that full stops are not followed by item commands, and that the end of sentences contains \end{itemize} as in Listing 396. This setting is actually an appended version of the betterFullStop from the fineTuning, detailed in Listing 559.

Listing 396 itemize.yaml

modifyLineBreaks:
    textWrapOptions:
        columns: 45
    oneSentencePerLine:
        sentencesEndWith:
            betterFullStop: 0
            other: |-
                (?x)                    
                (?:                             # new
                 (?:\R|\h)*\\item               # new
                )                               # new
                |
                (?:                     
                  \.\)                  
                  (?!\h*[a-z])          
                )                       
                |                       
                (?:                     
                  (?<!                  
                    (?:                 
                      (?:[eE]\.[gG])    
                      |                 
                      (?:[iI]\.[eE])    
                      |                 
                      (?:etc)           
                    )                   
                  )                     
                )                       
                \.                      
                (?:\h*\R*(?:\\end\{itemize\})?) # new
                (?!                     
                  (?:                   
                    [a-zA-Z0-9-~,]      
                    |                   
                    \),                 
                    |                   
                    \)\.                
                  )                     
                )                       

Upon running

latexindent.pl multiple-sentences6 -m -l=sentence-wrap1.yaml,itemize.yaml

we receive the output in Listing 397.

Listing 397 multiple-sentences6-mod3.tex using Listing 392 and Listing 396

Consider the following:
\begin{itemize}
	\item firstly.
	\item secondly.
\end{itemize}

Notice that the sentence has received indentation, and that the itemize code block has been found and indented correctly.

Text wrapping when using the oneSentencePerLine routine determines if it will remove line breaks while text wrapping, from the value of removeSentenceLineBreaks.

4.2.8. oneSentencePerLine: text wrapping and indenting sentences, when before/after

The text wrapping routine operates, by default, before the code blocks have been found, but this can be changed to after:

before means it is likely that the columns of wrapped text may exceed the value specified in columns;
after means it columns of wrapped text should not exceed the value specified in columns.

We demonstrate this in the following examples. See also Section 4.1.7.

Example 115

Let’s begin with the file in Listing 398.

Listing 398 multiple-sentences8.tex

This paragraph
has line breaks throughout its paragraph;
we would like to combine
the textwrapping
and paragraph removal routine.
\begin{myenv}
This paragraph
has line breaks throughout its paragraph;
we would like to combine
the textwrapping
and paragraph removal routine.
\end{myenv}

Using the settings given in Listing 400 and running the command

latexindent.pl multiple-sentences8 -o=+-mod1.tex -l=sentence-wrap2 -m

gives the output given in Listing 399.

Listing 399 multiple-sentences8-mod1.tex

This paragraph has line breaks
throughout its paragraph; we would
like to combine the textwrapping
and paragraph removal routine.
\begin{myenv}
   This paragraph has line breaks
   throughout its paragraph; we would
   like to combine the textwrapping
   and paragraph removal routine.
\end{myenv}
----|----|----|----|----|----|----|----|
   5   10   15   20   25   30   35   40

Listing 400 sentence-wrap2.yaml

defaultIndent: '   '
modifyLineBreaks:
    oneSentencePerLine:
        manipulateSentences: 1     
        textWrapSentences: 1
    textWrapOptions:
        columns: 35
        when: before  # <!-------

We note that, in Listing 399, that the wrapped text has exceeded the specified value of columns (35) given in Listing 400. We can affect this by changing when; we explore this next.

Example 116

We continue working with Listing 398.

Using the settings given in Listing 402 and running the command

latexindent.pl multiple-sentences8.tex -o=+-mod2.tex -l=sentence-wrap3 -m

gives the output given in Listing 401.

Listing 401 multiple-sentences8-mod2.tex

This paragraph has line breaks
throughout its paragraph; we would
like to combine the textwrapping
and paragraph removal routine.
\begin{myenv}
   This paragraph has line breaks
   throughout its paragraph; we
   would like to combine the
   textwrapping and paragraph
   removal routine.
\end{myenv}
----|----|----|----|----|----|----|----|
   5   10   15   20   25   30   35   40

Listing 402 sentence-wrap3.yaml

defaultIndent: '   '
modifyLineBreaks:
    oneSentencePerLine:
        manipulateSentences: 1     
        textWrapSentences: 1
    textWrapOptions:
        columns: 35
        when: after  # <!-------

We note that, in Listing 401, that the wrapped text has obeyed the specified value of columns (35) given in Listing 402.

4.2.9. oneSentencePerLine: text wrapping sentences and comments

We demonstrate the one sentence per line routine with respect to text wrapping comments. See also Section 4.1.8.

Example 117

Let’s begin with the file in Listing 403.

Listing 403 multiple-sentences9.tex

This paragraph% first comment
has line breaks throughout its paragraph;% second comment
we would like to combine% third comment
the textwrapping% fourth comment
and paragraph removal routine. % fifth comment

Using the settings given in Listing 405 and running the command

latexindent.pl multiple-sentences9 -o=+-mod1.tex -l=sentence-wrap4 -m

gives the output given in Listing 404.

Listing 404 multiple-sentences9-mod1.tex

This paragraph has line breaks
throughout its paragraph; we would
like to combine the textwrapping
and paragraph removal routine.
% first comment second comment
% third comment fourth comment
% fifth comment
----|----|----|----|----|----|----|----|
   5   10   15   20   25   30   35   40

Listing 405 sentence-wrap4.yaml

defaultIndent: '   '
modifyLineBreaks:
    oneSentencePerLine:
        manipulateSentences: 1     
        textWrapSentences: 1
    textWrapOptions:
        columns: 35
        comments: 
          wrap: 1  #<!-------

We note that, in Listing 404, that the sentences have been wrapped, and so too have the comments because of the annotated line in Listing 405.

4.3. Poly-switches

Every other field in the modifyLineBreaks field uses poly-switches, and can take one of the following integer values:

$-1$: remove mode: line breaks before or after the <part of thing> can be removed (assuming that preserveBlankLines is set to 0);
0: off mode: line breaks will not be modified for the <part of thing> under consideration;
1: add mode: a line break will be added before or after the <part of thing> under consideration, assuming that there is not already a line break before or after the <part of thing>;
2: comment then add mode: a comment symbol will be added, followed by a line break before or after the <part of thing> under consideration, assuming that there is not already a comment and line break before or after the <part of thing>;
3: add then blank line mode : a line break will be added before or after the <part of thing> under consideration, assuming that there is not already a line break before or after the <part of thing>, followed by a blank line;
4: add blank line mode ; a blank line will be added before or after the <part of thing> under consideration, even if the <part of thing> is already on its own line.

In the above, <part of thing> refers to either the begin statement, body or end statement of the code blocks detailed in Table 2. All poly-switches are off by default; latexindent.pl searches first of all for per-name settings, and then followed by global per-thing settings.

4.3.1. Poly-switches for environments

We start by viewing a snippet of defaultSettings.yaml in Listing 406; note that it contains global settings (immediately after the environments field) and that per-name settings are also allowed – in the case of Listing 406, settings for equation* have been specified for demonstration. Note that all poly-switches are off (set to 0) by default.

Listing 406 environments

  environments:
    BeginStartsOnOwnLine: 0             # -1,0,1,2,3,4
    BodyStartsOnOwnLine: 0              # -1,0,1,2,3,4
    EndStartsOnOwnLine: 0               # -1,0,1,2,3,4
    EndFinishesWithLineBreak: 0         # -1,0,1,2,3,4
    # equation*:
    #     BeginStartsOnOwnLine: 0       # -1,0,1,2,3,4
    #     BodyStartsOnOwnLine: 0        # -1,0,1,2,3,4
    #     EndStartsOnOwnLine: 0         # -1,0,1,2,3,4
    #     EndFinishesWithLineBreak: 0   # -1,0,1,2,3,4

Let’s begin with the simple example given in Listing 407; note that we have annotated key parts of the file using ♠, ♥, ◆ and ♣, these will be related to fields specified in Listing 406.

Listing 407 env-mlb1.tex

before words♠ \begin{myenv}♥body of myenv◆\end{myenv}♣ after words

4.3.1.1. Adding line breaks: BeginStartsOnOwnLine and BodyStartsOnOwnLine

Example 118

Let’s explore BeginStartsOnOwnLine and BodyStartsOnOwnLine in Listing 408 and Listing 409, and in particular, let’s allow each of them in turn to take a value of $1$.

Listing 408 env-mlb1.yaml

modifyLineBreaks:
    environments:
        BeginStartsOnOwnLine: 1

Listing 409 env-mlb2.yaml

modifyLineBreaks:
    environments:
        BodyStartsOnOwnLine: 1

After running the following commands,

latexindent.pl -m env-mlb.tex -l env-mlb1.yaml
latexindent.pl -m env-mlb.tex -l env-mlb2.yaml

the output is as in Listing 410 and Listing 411 respectively.

Listing 410 env-mlb.tex using Listing 408

before words
\begin{myenv}body of myenv\end{myenv} after words

Listing 411 env-mlb.tex using Listing 409

before words \begin{myenv}
	body of myenv\end{myenv} after words

There are a couple of points to note:

in Listing 410 a line break has been added at the point denoted by ♠ in Listing 407; no other line breaks have been changed;
in Listing 411 a line break has been added at the point denoted by ♥ in Listing 407; furthermore, note that the body of myenv has received the appropriate (default) indentation.

Example 119

Let’s now change each of the 1 values in Listing 408 and Listing 409 so that they are $2$ and save them into env-mlb3.yaml and env-mlb4.yaml respectively (see Listing 412 and Listing 413).

Listing 412 env-mlb3.yaml

modifyLineBreaks:
    environments:
        BeginStartsOnOwnLine: 2

Listing 413 env-mlb4.yaml

modifyLineBreaks:
    environments:
        BodyStartsOnOwnLine: 2

Upon running the commands

latexindent.pl -m env-mlb.tex -l env-mlb3.yaml
latexindent.pl -m env-mlb.tex -l env-mlb4.yaml

we obtain Listing 414 and Listing 415.

Listing 414 env-mlb.tex using Listing 412

before words%
\begin{myenv}body of myenv\end{myenv} after words

Listing 415 env-mlb.tex using Listing 413

before words \begin{myenv}%
	body of myenv\end{myenv} after words

Note that line breaks have been added as in Listing 410 and Listing 411, but this time a comment symbol has been added before adding the line break; in both cases, trailing horizontal space has been stripped before doing so.

Example 120

Let’s now change each of the 1 values in Listing 408 and Listing 409 so that they are $3$ and save them into env-mlb5.yaml and env-mlb6.yaml respectively (see Listing 416 and Listing 417).

Listing 416 env-mlb5.yaml

modifyLineBreaks:
    environments:
        BeginStartsOnOwnLine: 3

Listing 417 env-mlb6.yaml

modifyLineBreaks:
    environments:
        BodyStartsOnOwnLine: 3

Upon running the commands

latexindent.pl -m env-mlb.tex -l env-mlb5.yaml
latexindent.pl -m env-mlb.tex -l env-mlb6.yaml

we obtain Listing 418 and Listing 419.

Listing 418 env-mlb.tex using Listing 416

before words

\begin{myenv}body of myenv\end{myenv} after words

Listing 419 env-mlb.tex using Listing 417

before words \begin{myenv}

	body of myenv\end{myenv} after words

Note that line breaks have been added as in Listing 410 and Listing 411, but this time a blank line has been added after adding the line break.

Example 121

Let’s now change each of the 1 values in Listing 416 and Listing 417 so that they are $4$ and save them into env-beg4.yaml and env-body4.yaml respectively (see Listing 420 and Listing 421).

Listing 420 env-beg4.yaml

modifyLineBreaks:
    environments:
        BeginStartsOnOwnLine: 4

Listing 421 env-body4.yaml

modifyLineBreaks:
    environments:
        BodyStartsOnOwnLine: 4

We will demonstrate this poly-switch value using the code in Listing 422.

Listing 422 env-mlb1.tex

before words 
\begin{myenv}
body of myenv
\end{myenv} 
after words

Upon running the commands

latexindent.pl -m env-mlb1.tex -l env-beg4.yaml
latexindent.pl -m env-mlb.1tex -l env-body4.yaml

then we receive the respective outputs in Listing 423 and Listing 424.

Listing 423 env-mlb1.tex using Listing 420

before words

\begin{myenv}
	body of myenv
\end{myenv}
after words

Listing 424 env-mlb1.tex using Listing 421

before words
\begin{myenv}

	body of myenv
\end{myenv}
after words

We note in particular that, by design, for this value of the poly-switches:

in Listing 423 a blank line has been inserted before the \begin statement, even though the \begin statement was already on its own line;
in Listing 424 a blank line has been inserted before the beginning of the body, even though it already began on its own line.

4.3.1.2. Adding line breaks: EndStartsOnOwnLine and EndFinishesWithLineBreak

Example 122

Let’s explore EndStartsOnOwnLine and EndFinishesWithLineBreak in Listing 425 and Listing 426, and in particular, let’s allow each of them in turn to take a value of $1$.

Listing 425 env-mlb7.yaml

modifyLineBreaks:
    environments:
        EndStartsOnOwnLine: 1

Listing 426 env-mlb8.yaml

modifyLineBreaks:
    environments:
        EndFinishesWithLineBreak: 1

After running the following commands,

latexindent.pl -m env-mlb.tex -l env-mlb7.yaml
latexindent.pl -m env-mlb.tex -l env-mlb8.yaml

the output is as in Listing 427 and Listing 428.

Listing 427 env-mlb.tex using Listing 425

before words \begin{myenv}body of myenv
\end{myenv} after words

Listing 428 env-mlb.tex using Listing 426

before words \begin{myenv}body of myenv\end{myenv}
after words

There are a couple of points to note:

in Listing 427 a line break has been added at the point denoted by ◆ in Listing 407; no other line breaks have been changed and the \end{myenv} statement has not received indentation (as intended);
in Listing 428 a line break has been added at the point denoted by ♣ in Listing 407.

Example 123

Let’s now change each of the 1 values in Listing 425 and Listing 426 so that they are $2$ and save them into env-mlb9.yaml and env-mlb10.yaml respectively (see Listing 429 and Listing 430).

Listing 429 env-mlb9.yaml

modifyLineBreaks:
    environments:
        EndStartsOnOwnLine: 2

Listing 430 env-mlb10.yaml

modifyLineBreaks:
    environments:
        EndFinishesWithLineBreak: 2

Upon running the commands

latexindent.pl -m env-mlb.tex -l env-mlb9.yaml
latexindent.pl -m env-mlb.tex -l env-mlb10.yaml

we obtain Listing 431 and Listing 432.

Listing 431 env-mlb.tex using Listing 429

before words \begin{myenv}body of myenv%
\end{myenv} after words

Listing 432 env-mlb.tex using Listing 430

before words \begin{myenv}body of myenv\end{myenv}%
after words

Note that line breaks have been added as in Listing 427 and Listing 428, but this time a comment symbol has been added before adding the line break; in both cases, trailing horizontal space has been stripped before doing so.

Example 124

Let’s now change each of the 1 values in Listing 425 and Listing 426 so that they are $3$ and save them into env-mlb11.yaml and env-mlb12.yaml respectively (see Listing 433 and Listing 434).

Listing 433 env-mlb11.yaml

modifyLineBreaks:
    environments:
        EndStartsOnOwnLine: 3

Listing 434 env-mlb12.yaml

modifyLineBreaks:
    environments:
        EndFinishesWithLineBreak: 3

Upon running the commands

latexindent.pl -m env-mlb.tex -l env-mlb11.yaml
latexindent.pl -m env-mlb.tex -l env-mlb12.yaml

we obtain Listing 435 and Listing 436.

Listing 435 env-mlb.tex using Listing 433

before words \begin{myenv}body of myenv

\end{myenv} after words

Listing 436 env-mlb.tex using Listing 434

before words \begin{myenv}body of myenv\end{myenv}

after words

Note that line breaks have been added as in Listing 427 and Listing 428, and that a blank line has been added after the line break.

Example 125

Let’s now change each of the 1 values in Listing 433 and Listing 434 so that they are $4$ and save them into env-end4.yaml and env-end-f4.yaml respectively (see Listing 437 and Listing 438).

Listing 437 env-end4.yaml

modifyLineBreaks:
    environments:
        EndStartsOnOwnLine: 4

Listing 438 env-end-f4.yaml

modifyLineBreaks:
    environments:
        EndFinishesWithLineBreak: 4

We will demonstrate this poly-switch value using the code from Listing 422.

Upon running the commands

latexindent.pl -m env-mlb1.tex -l env-end4.yaml
latexindent.pl -m env-mlb.1tex -l env-end-f4.yaml

then we receive the respective outputs in Listing 439 and Listing 440.

Listing 439 env-mlb1.tex using Listing 437

before words
\begin{myenv}
	body of myenv

\end{myenv}
after words

Listing 440 env-mlb1.tex using Listing 438

before words
\begin{myenv}
	body of myenv
\end{myenv}

after words

We note in particular that, by design, for this value of the poly-switches:

in Listing 439 a blank line has been inserted before the \end statement, even though the \end statement was already on its own line;
in Listing 440 a blank line has been inserted after the \end statement, even though it already began on its own line.

4.3.1.3. poly-switches 1, 2, and 3 only add line breaks when necessary

If you ask latexindent.pl to add a line break (possibly with a comment) using a poly-switch value of $1$ (or $2$ or $3$), it will only do so if necessary.

Example 126

For example, if you process the file in Listing 441 using poly-switch values of 1, 2, or 3, it will be left unchanged.

Listing 441 env-mlb2.tex

before words 
\begin{myenv}
  body of myenv
\end{myenv} 
after words

Listing 442 env-mlb3.tex

before words 
\begin{myenv}  %
  body of myenv%
\end{myenv}% 
after words

Setting the poly-switches to a value of $4$ instructs latexindent.pl to add a line break even if the <part of thing> is already on its own line; see Listing 423 and Listing 424 and Listing 439 and Listing 440.

Example 127

In contrast, the output from processing the file in Listing 442 will vary depending on the poly-switches used; in Listing 443 you’ll see that the comment symbol after the \begin{myenv} has been moved to the next line, as BodyStartsOnOwnLine is set to 1. In Listing 444 you’ll see that the comment has been accounted for correctly because BodyStartsOnOwnLine has been set to 2, and the comment symbol has not been moved to its own line. You’re encouraged to experiment with Listing 442 and by setting the other poly-switches considered so far to 2 in turn.

Listing 443 env-mlb3.tex using Listing 409

before words
\begin{myenv}
	%
	body of myenv%
\end{myenv}% 
after words

Listing 444 env-mlb3.tex using Listing 413

before words
\begin{myenv}  %
	body of myenv%
\end{myenv}% 
after words

The details of the discussion in this section have concerned global poly-switches in the environments field; each switch can also be specified on a per-name basis, which would take priority over the global values; with reference to Listing 406, an example is shown for the equation* environment.

4.3.1.4. Removing line breaks (poly-switches set to $-1$)

Setting poly-switches to $-1$ tells latexindent.pl to remove line breaks of the <part of the thing>, if necessary.

Example 128

We will consider the example code given in Listing 445, noting in particular the positions of the line break highlighters, ♠, ♥, ◆ and ♣, together with the associated YAML files in Listing 446 – Listing 449.

Listing 445 env-mlb4.tex

before words♠
\begin{myenv}♥
body of myenv◆
\end{myenv}♣
after words

After

Listing 446 env-mlb13.yaml

modifyLineBreaks:
    environments:
        BeginStartsOnOwnLine: -1

Listing 447 env-mlb14.yaml

modifyLineBreaks:
    environments:
        BodyStartsOnOwnLine: -1

Listing 448 env-mlb15.yaml

modifyLineBreaks:
    environments:
        EndStartsOnOwnLine: -1

Listing 449 env-mlb16.yaml

modifyLineBreaks:
    environments:
        EndFinishesWithLineBreak: -1

running the commands

latexindent.pl -m env-mlb4.tex -l env-mlb13.yaml
latexindent.pl -m env-mlb4.tex -l env-mlb14.yaml
latexindent.pl -m env-mlb4.tex -l env-mlb15.yaml
latexindent.pl -m env-mlb4.tex -l env-mlb16.yaml

we obtain the respective output in Listing 450 – Listing 453.

Listing 450 env-mlb4.tex using Listing 446

before words\begin{myenv}
	body of myenv
\end{myenv}
after words

Listing 451 env-mlb4.tex using Listing 447

before words
\begin{myenv}body of myenv
\end{myenv}
after words

Listing 452 env-mlb4.tex using Listing 448

before words
\begin{myenv}
	body of myenv\end{myenv}
after words

Listing 453 env-mlb4.tex using Listing 449

before words
\begin{myenv}
	body of myenv
\end{myenv}after words

Notice that in:

Listing 450 the line break denoted by ♠ in Listing 445 has been removed;
Listing 451 the line break denoted by ♥ in Listing 445 has been removed;
Listing 452 the line break denoted by ◆ in Listing 445 has been removed;
Listing 453 the line break denoted by ♣ in Listing 445 has been removed.

We examined each of these cases separately for clarity of explanation, but you can combine all of the YAML settings in Listing 446 – Listing 449 into one file; alternatively, you could tell latexindent.pl to load them all by using the following command, for example

latexindent.pl -m env-mlb4.tex -l env-mlb13.yaml,env-mlb14.yaml,env-mlb15.yaml,env-mlb16.yaml

which gives the output in Listing 407.

4.3.1.5. About trailing horizontal space

Recall that on page yaml:removeTrailingWhitespace we discussed the YAML field removeTrailingWhitespace, and that it has two (binary) switches to determine if horizontal space should be removed beforeProcessing and afterProcessing. The beforeProcessing is particularly relevant when considering the -m switch.

Example 129

We consider the file shown in Listing 454, which highlights trailing spaces.

Listing 454 env-mlb5.tex

before words   ♠
\begin{myenv}           ♥
body of myenv      ◆
\end{myenv}     ♣
after words

The

Listing 455 removeTWS-before.yaml

removeTrailingWhitespace:
    beforeProcessing: 1

output from the following commands

latexindent.pl -m env-mlb5.tex -l env-mlb13,env-mlb14,env-mlb15,env-mlb16
latexindent.pl -m env-mlb5.tex -l env-mlb13,env-mlb14,env-mlb15,env-mlb16,removeTWS-before

is shown, respectively, in Listing 456 and Listing 457; note that the trailing horizontal white space has been preserved (by default) in Listing 456, while in Listing 457, it has been removed using the switch specified in Listing 455.

Listing 456 env-mlb5.tex using Listing 450 – Listing 453

before words   \begin{myenv}           body of myenv      \end{myenv}     after words

Listing 457 env-mlb5.tex using Listing 450 – Listing 453 and Listing 455

before words\begin{myenv}body of myenv\end{myenv}after words

4.3.1.6. poly-switch line break removal and blank lines

Example 130

Now let’s consider the file in Listing 458, which contains blank lines.

Listing 458 env-mlb6.tex

before words♠

\begin{myenv}♥

body of myenv◆

\end{myenv}♣

after words

Upon

Listing 459 UnpreserveBlankLines.yaml

modifyLineBreaks:
    preserveBlankLines: 0

running the following commands

latexindent.pl -m env-mlb6.tex -l env-mlb13,env-mlb14,env-mlb15,env-mlb16
latexindent.pl -m env-mlb6.tex -l env-mlb13,env-mlb14,env-mlb15,env-mlb16,UnpreserveBlankLines

we receive the respective outputs in Listing 460 and Listing 461. In Listing 460 we see that the multiple blank lines have each been condensed into one blank line, but that blank lines have not been removed by the poly-switches – this is because, by default, preserveBlankLines is set to 1. By contrast, in Listing 461, we have allowed the poly-switches to remove blank lines because, in Listing 459, we have set preserveBlankLines to 0.

Listing 460 env-mlb6.tex using Listing 450 – Listing 453

before words

\begin{myenv}

	body of myenv

\end{myenv}

after words

Listing 461 env-mlb6.tex using Listing 450 – Listing 453 and Listing 459

before words\begin{myenv}body of myenv\end{myenv}after words

Example 131

We can explore this further using the blank-line poly-switch value of $3$; let’s use the file given in Listing 462.

Listing 462 env-mlb7.tex

\begin{one} one text \end{one} \begin{two} two text \end{two}

Upon running the following commands

latexindent.pl -m env-mlb7.tex -l env-mlb12.yaml,env-mlb13.yaml
latexindent.pl -m env-mlb7.tex -l env-mlb13,env-mlb14,UnpreserveBlankLines

we receive the outputs given in Listing 463 and Listing 464.

Listing 463 env-mlb7-preserve.tex

\begin{one} one text \end{one}

\begin{two} two text \end{two}

Listing 464 env-mlb7-no-preserve.tex

\begin{one} one text \end{one} \begin{two} two text \end{two}

Notice that in:

Listing 463 that \end{one} has added a blank line, because of the value of EndFinishesWithLineBreak in Listing 434, and even though the line break ahead of \begin{two} should have been removed (because of BeginStartsOnOwnLine in Listing 446), the blank line has been preserved by default;
Listing 464, by contrast, has had the additional line-break removed, because of the settings in Listing 459.

4.3.2. Poly-switches for double backslash

With reference to lookForAlignDelims (see Listing 55) you can specify poly-switches to dictate the line-break behaviour of double backslashes in environments (Listing 57), commands (Listing 124), or special code blocks (Listing 132). 1

Consider the code given in Listing 465.

Listing 465 tabular3.tex

\begin{tabular}{cc}
 1 & 2 ★\\□ 3 & 4 ★\\□
\end{tabular}

Referencing Listing 465:

DBS stands for double backslash;
line breaks ahead of the double backslash are annotated by ★, and are controlled by DBSStartsOnOwnLine;
line breaks after the double backslash are annotated by □, and are controlled by DBSFinishesWithLineBreak.

Let’s explore each of these in turn.

4.3.2.1. Double backslash starts on own line

Example 132

We explore DBSStartsOnOwnLine (★ in Listing 465); starting with the code in Listing 465, together with the YAML files given in Listing 467 and Listing 469 and running the following commands

latexindent.pl -m tabular3.tex -l DBS1.yaml
latexindent.pl -m tabular3.tex -l DBS2.yaml

then we receive the respective output given in Listing 466 and Listing 468.

Listing 466 tabular3.tex using Listing 467

\begin{tabular}{cc}
	1 & 2
	\\ 3 & 4
	\\
\end{tabular}

Listing 467 DBS1.yaml

modifyLineBreaks:
    environments:
        DBSStartsOnOwnLine: 1

Listing 468 tabular3.tex using Listing 469

\begin{tabular}{cc}
	1 & 2 %
	\\ 3 & 4 %
	\\
\end{tabular}

Listing 469 DBS2.yaml

modifyLineBreaks:
    environments:
        tabular:
            DBSStartsOnOwnLine: 2

We note that

Listing 467 specifies DBSStartsOnOwnLine for every environment (that is within lookForAlignDelims, Listing 58); the double backslashes from Listing 465 have been moved to their own line in Listing 466;
Listing 469 specifies DBSStartsOnOwnLine on a per-name basis for tabular (that is within lookForAlignDelims, Listing 58); the double backslashes from Listing 465 have been moved to their own line in Listing 468, having added comment symbols before moving them.

Example 133

We can combine DBS poly-switches with, for example, the alignContentAfterDoubleBackSlash in Section 3.5.5.

For example, starting with the file Listing 470, and using the settings in Listing 120 and Listing 122 and running

latexindent.pl -s -m -l alignContentAfterDBS1.yaml,DBS1.yaml tabular6.tex -o=+-mod1
latexindent.pl -s -m -l alignContentAfterDBS2.yaml,DBS1.yaml tabular6.tex -o=+-mod2

gives the respective outputs shown in Listing 471 and Listing 472.

Listing 470 tabular6.tex

\begin{tabular}{cc}
 1&22\\333&4444\\55555&666666
\end{tabular}

Listing 471 tabular6-mod1.tex

\begin{tabular}{cc}
	   1     & 22
	\\ 333   & 4444
	\\ 55555 & 666666
\end{tabular}

Listing 472 tabular6-mod2.tex

\begin{tabular}{cc}
	     1     & 22
	\\   333   & 4444
	\\   55555 & 666666
\end{tabular}

We note that:

in Listing 471 the content after the double back slash has been aligned;
in Listing 472 we see that 3 spaces have been added after the double back slash.

4.3.2.2. Double backslash finishes with line break

Example 134

Let’s now explore DBSFinishesWithLineBreak (□ in Listing 465); starting with the code in Listing 465, together with the YAML files given in Listing 474 and Listing 476 and running the following commands

latexindent.pl -m tabular3.tex -l DBS3.yaml
latexindent.pl -m tabular3.tex -l DBS4.yaml

then we receive the respective output given in Listing 473 and Listing 475.

Listing 473 tabular3.tex using Listing 474

\begin{tabular}{cc}
	1 & 2 \\
	3 & 4 \\
\end{tabular}

Listing 474 DBS3.yaml

modifyLineBreaks:
    environments:
        DBSFinishesWithLineBreak: 1

Listing 475 tabular3.tex using Listing 476

\begin{tabular}{cc}
	1 & 2 \\%
	3 & 4 \\
\end{tabular}

Listing 476 DBS4.yaml

modifyLineBreaks:
 environments:
   tabular:
     DBSFinishesWithLineBreak: 2

We note that

Listing 474 specifies DBSFinishesWithLineBreak for every environment (that is within lookForAlignDelims, Listing 58); the code following the double backslashes from Listing 465 has been moved to their own line in Listing 473;
Listing 476 specifies DBSFinishesWithLineBreak on a per-name basis for tabular (that is within lookForAlignDelims, Listing 58); the first double backslashes from Listing 465 have moved code following them to their own line in Listing 475, having added comment symbols before moving them; the final double backslashes have not added a line break as they are at the end of the body within the code block.

4.3.2.3. Double backslash poly-switches for specialBeginEnd

Example 135

Let’s explore the double backslash poly-switches for code blocks within specialBeginEnd code blocks (Listing 130); we begin with the code within Listing 477.

Listing 477 special4.tex

\< a& =b  \\ & =c\\ & =d\\ & =e \>

Upon using the YAML settings in Listing 479, and running the command

latexindent.pl -m special4.tex -l DBS5.yaml

then we receive the output given in Listing 478.

Listing 478 special4.tex using Listing 479

\<
	a & =b \\
	  & =c \\
	  & =d \\
	  & =e %
\>

Listing 479 DBS5.yaml

specialBeginEnd:
  - name: cmhMath
    begin: '\\<'
    end: '\\>'
lookForAlignDelims:
    cmhMath: 1
modifyLineBreaks:
 specialBeginEnd:
  cmhMath:
   DBSFinishesWithLineBreak: 1
   SpecialBodyStartsOnOwnLine: 1
   SpecialEndStartsOnOwnLine: 2

There are a few things to note:

in Listing 479 we have specified cmhMath within lookForAlignDelims; without this, the double backslash poly-switches would be ignored for this code block;
the DBSFinishesWithLineBreak poly-switch has controlled the line breaks following the double backslashes;
the SpecialEndStartsOnOwnLine poly-switch has controlled the addition of a comment symbol, followed by a line break, as it is set to a value of 2.

4.3.2.4. Double backslash poly-switches for optional and mandatory arguments

For clarity, we provide a demonstration of controlling the double backslash poly-switches for optional and mandatory arguments.

Example 136

We use with the code in Listing 480.

Listing 480 mycommand2.tex

\mycommand [
	1&2   &3\\ 4&5&6]{
7&8   &9\\ 10&11&12
}

Upon using the YAML settings in Listing 482 and Listing 484, and running the command

latexindent.pl -m mycommand2.tex -l DBS6.yaml
latexindent.pl -m mycommand2.tex -l DBS7.yaml

then we receive the output given in Listing 481 and Listing 483.

Listing 481 mycommand2.tex using Listing 482

\mycommand [
	1 & 2 & 3 %
	\\%
	4 & 5 & 6]{
	7 & 8 & 9 \\ 10&11&12
}

Listing 482 DBS6.yaml

lookForAlignDelims:
    mycommand: 1
modifyLineBreaks:
    optionalArguments:
        DBSStartsOnOwnLine: 2
        DBSFinishesWithLineBreak: 2

Listing 483 mycommand2.tex using Listing 484

\mycommand [
	1 & 2 & 3 \\ 4&5&6]{
	7  & 8  & 9  %
	\\%
	10 & 11 & 12
}

Listing 484 DBS7.yaml

lookForAlignDelims:
    mycommand: 1
modifyLineBreaks:
    mandatoryArguments:
        DBSStartsOnOwnLine: 2
        DBSFinishesWithLineBreak: 2

4.3.2.5. Double backslash optional square brackets

The pattern matching for the double backslash will also, optionally, allow trailing square brackets that contain a measurement of vertical spacing, for example \\[3pt].

Example 137

For example, beginning with the code in Listing 485

Listing 485 pmatrix3.tex

\begin{pmatrix}
1 & 2 \\[2pt] 3 & 4 \\ [ 3 ex] 5&6\\[    4  pt   ] 7 & 8 
\end{pmatrix}

and running the following command, using Listing 474,

latexindent.pl -m pmatrix3.tex -l DBS3.yaml

then we receive the output given in Listing 486.

Listing 486 pmatrix3.tex using Listing 474

\begin{pmatrix}
	1 & 2 \\[2pt]
	3 & 4 \\ [ 3 ex]
	5 & 6 \\[    4  pt   ]
	7 & 8
\end{pmatrix}

You can customise the pattern for the double backslash by exploring the fine tuning field detailed in Listing 559.

4.3.3. Poly-switches for commas

With reference to Table 3 you can specify poly-switches to dictate the line-break behaviour of commas in arguments for code blocks that have arguments: commands, namedGroupingBracesBrackets, keyEqualsValuesBracesBrackets and UnNamedGroupingBracesBrackets.

Consider the code given in Listing 487.

Listing 487 comma1.tex

\mycommand{1★,□2★,□3}[4★,□5★,□6]

Referencing Listing 487:

line breaks ahead of the comma are annotated by ★, and are controlled by CommaStartsOnOwnLine;
line breaks after the comma are annotated by □, and are controlled by CommaFinishesWithLineBreak.

Let’s explore each of these in turn.

4.3.3.1. Comma starts on own line

Example 138

We explore CommaStartsOnOwnLine (★ in Listing 487); starting with the code in Listing 487, together with the YAML files given in Listing 489 and Listing 491 and running the following commands

latexindent.pl comma1.tex -l comma1.yaml
latexindent.pl comma1.tex -l comma2.yaml

then we receive the respective output given in Listing 488 and Listing 490.

Listing 488 comma1-mod1.tex

\mycommand{1
	,2
	,3}[4
	,5
	,6]

Listing 489 comma1.yaml

switchesViaYaml:
  mSwitch: 1
modifyLineBreaks:
  optionalArguments:
    CommaStartsOnOwnLine: 1
  mandatoryArguments:
    CommaStartsOnOwnLine: 1

Listing 490 comma1-mod2.tex

\mycommand{1%
	,2%
	,3}[4%
	,5%
	,6]

Listing 491 comma2.yaml

switchesViaYaml:
  mSwitch: 1
modifyLineBreaks:
  optionalArguments:
    mycommand:
      CommaStartsOnOwnLine: 2
  mandatoryArguments:
    mycommand:
      CommaStartsOnOwnLine: 2

We note that

Listing 489 specifies CommaStartsOnOwnLine for every mandatory and optional argument; the commas Listing 487 have been moved to their own line in Listing 488;
Listing 491 specifies CommaStartsOnOwnLine on a per-name basis for mycommand; the commas from Listing 487 have been moved to their own line in Listing 490, having added comment symbols before moving them.

4.3.3.2. Comma finishes with line break

Example 139

Let’s now explore CommaFinishesWithLineBreak (□ in Listing 487); starting with the code in Listing 487, together with the YAML files given in Listing 493 and Listing 495 and running the following commands

latexindent.pl comma1.tex -l comma3.yaml
latexindent.pl comma1.tex -l comma4.yaml

then we receive the respective output given in Listing 492 and Listing 494.

Listing 492 comma1-mod3.tex

\mycommand{1,
	2,
	3}[4,
	5,
	6]

Listing 493 comma3.yaml

switchesViaYaml:
  mSwitch: 1
modifyLineBreaks:
  optionalArguments:
    CommaFinishesWithLineBreak: 1
  mandatoryArguments:
    CommaFinishesWithLineBreak: 1

Listing 494 comma1-mod4.tex

\mycommand{1,%
	2,%
	3}[4,%
	5,%
	6]

Listing 495 comma4.yaml

switchesViaYaml:
  mSwitch: 1
modifyLineBreaks:
  optionalArguments:
    mycommand:
      CommaFinishesWithLineBreak: 2
  mandatoryArguments:
    mycommand:
      CommaFinishesWithLineBreak: 2

We note that

Listing 493 specifies CommaFinishesWithLineBreak for every mandatory and optional argument; the code following the commas from Listing 487 has been moved to their own line in Listing 492;
Listing 495 specifies CommaFinishesWithLineBreak on a per-name basis for mycommand; the code following the commas has been moved to their own line in Listing 494, having added comment symbols before moving them.

4.3.4. Poly-switches for other code blocks

Rather than repeat the examples shown for the environment code blocks (in Section 4.3.1), we choose to detail the poly-switches for all other code blocks in Table 3; note that each and every one of these poly-switches is off by default, i.e, set to 0.

Note also that, by design, line breaks involving, filecontents and ‘comment-marked’ code blocks (Listing 125) can not be modified using latexindent.pl. However, there are two poly-switches available for verbatim code blocks: environments (Listing 35), commands (Listing 36) and specialBeginEnd (Listing 145).

Table 3 Poly-switch mappings for all code-block types
Code block	Sample
environment	`before words`♠	♠	BeginStartsOnOwnLine
	`\begin{myenv}`♥	♥	BodyStartsOnOwnLine
	`body of myenv`◆	◆	EndStartsOnOwnLine
	`\end{myenv}`♣	♣	EndFinishesWithLineBreak
	`after words`
ifelsefi	`before words`♠	♠	IfStartsOnOwnLine
	`\if...`♥	♥	BodyStartsOnOwnLine
	`body of if/or statement`▲	▲	OrStartsOnOwnLine
	`\or`▼	▼	OrFinishesWithLineBreak
	`body of if/or statement`★	★	ElseStartsOnOwnLine
	`\else`□	□	ElseFinishesWithLineBreak
	`body of else statement`◆	◆	FiStartsOnOwnLine
	`\fi`♣	♣	FiFinishesWithLineBreak
	`after words`
optionalArguments	`...`♠	♠	LSqBStartsOnOwnLine 2
	`[`♥	♥	OptArgBodyStartsOnOwnLine
	`value before comma`★,	★	CommaStartsOnOwnLine
	□	□	CommaFinishesWithLineBreak
	`end of body of opt arg`◆	◆	RSqBStartsOnOwnLine
	`]`♣	♣	RSqBFinishesWithLineBreak
	`...`
mandatoryArguments	`...`♠	♠	LCuBStartsOnOwnLine 3
	`\{`♥	♥	MandArgBodyStartsOnOwnLine
	`value before comma`★,	★	CommaStartsOnOwnLine
	□	□	CommaFinishesWithLineBreak
	`end of body of mand arg`◆	◆	RCuBStartsOnOwnLine
	`}`♣	♣	RCuBFinishesWithLineBreak
	`...`
commands	`before words`♠	♠	CommandStartsOnOwnLine
	`\mycommand`
	<arguments>
namedGroupingBracesBrackets	before words♠	♠	NameStartsOnOwnLine
	myname
	<braces/brackets>
keyEqualsValuesBracesBrackets	before words♠	♠	KeyStartsOnOwnLine
	key●=♥	●	EqualsStartsOnOwnLine
	<braces/brackets>	♥	EqualsFinishesWithLineBreak
items	before words♠	♠	ItemStartsOnOwnLine
	`\item`♥	♥	ItemFinishesWithLineBreak
	`...`
specialBeginEnd	before words♠	♠	SpecialBeginStartsOnOwnLine
	`\[`♥	♥	SpecialBodyStartsOnOwnLine
	`body of special/middle`★	★	SpecialMiddleStartsOnOwnLine
	`\middle`□	□	SpecialMiddleFinishesWithLineBreak
	body of special/middle ◆	◆	SpecialEndStartsOnOwnLine
	`\]`♣	♣	SpecialEndFinishesWithLineBreak
	after words
verbatim	before words♠`\begin{verbatim}`	♠	VerbatimBeginStartsOnOwnLine
	body of verbatim `\end{verbatim}`♣	♣	VerbatimEndFinishesWithLineBreak
	after words

4.3.5. Conflicting poly-switches: sequential code blocks

It is very easy to have conflicting poly-switches. The most poly-switch corresponding to the most-recently-found code block will be respected.

Example 140

We use the Listing 496

Listing 496 mycommand1.tex

\mycommand
{
mand arg text
mand arg text}
{
mand arg text
mand arg text}

and consider the YAML settings given in Listing 498. The output from running

latexindent.pl -m -l=mycom-mlb4.yaml mycommand1.tex

is given in Listing 498.

Listing 497 mycommand1.tex using Listing 498

\mycommand{
	mand arg text
	mand arg text}{
	mand arg text
	mand arg text}

Listing 498 mycom-mlb4.yaml

modifyLineBreaks:
    mandatoryArguments:
        LCuBStartsOnOwnLine: -1
        RCuBFinishesWithLineBreak: 1

Studying Listing 498, we see that the two poly-switches are at opposition with one another:

on the one hand, LCuBStartsOnOwnLine should not start on its own line (as poly-switch is set to $-1$);
on the other hand, RCuBFinishesWithLineBreak should finish with a line break.

So, which should win the conflict? As demonstrated in Listing 497, it is clear that LCuBStartsOnOwnLine won this conflict, and the reason is that the second argument was processed after the first – in general, the most recently-processed code block and associated poly-switch takes priority.

Example 141

We can explore this further by considering the YAML settings in Listing 500; upon running the command

latexindent.pl -m -l=mycom-mlb5.yaml mycommand1.tex

we obtain the output given in Listing 499.

Listing 499 mycommand1.tex using Listing 500

\mycommand
{
	mand arg text
	mand arg text}
{
	mand arg text
	mand arg text}

Listing 500 mycom-mlb5.yaml

modifyLineBreaks:
  mandatoryArguments:
    LCuBStartsOnOwnLine: 1
    RCuBFinishesWithLineBreak: -1

As previously, the most-recently-processed code block takes priority – as before, the second (i.e, last) argument.

Exploring this further, we consider the YAML settings in Listing 502, and run the command

latexindent.pl -m -l=mycom-mlb6.yaml mycommand1.tex

which gives the output in Listing 501.

Listing 501 mycommand1.tex using Listing 502

\mycommand
{
	mand arg text
	mand arg text}%
{
	mand arg text
	mand arg text}

Listing 502 mycom-mlb6.yaml

modifyLineBreaks:
  mandatoryArguments:
    LCuBStartsOnOwnLine: 2
    RCuBFinishesWithLineBreak: -1

Note that a % has been added to the trailing first }; this is because:

while processing the first argument, the trailing line break has been removed (RCuBFinishesWithLineBreak set to $-1$);
while processing the second argument, latexindent.pl finds that it does not begin on its own line, and so because LCuBStartsOnOwnLine is set to $2$, it adds a comment, followed by a line break.

4.3.6. Conflicting poly-switches: nested code blocks

Example 142

Now let’s consider an example when nested code blocks have conflicting poly-switches; we’ll use the code in Listing 503, noting that it contains nested environments.

Listing 503 nested-env.tex

\begin{one}
one text
\begin{two}
two text
\end{two}
\end{one}

Let’s use the YAML settings given in Listing 505, which upon running the command

latexindent.pl -m -l=nested-env-mlb1.yaml nested-env.tex

gives the output in Listing 504.

Listing 504 nested-env.tex using Listing 505

\begin{one}
	one text
	\begin{two}
		two text\end{two}\end{one}

Listing 505 nested-env-mlb1.yaml

modifyLineBreaks:
    environments:
        EndStartsOnOwnLine: -1
        EndFinishesWithLineBreak: 1

In Listing 504, let’s first of all note that both environments have received the appropriate (default) indentation; secondly, note that the poly-switch EndStartsOnOwnLine appears to have won the conflict, as \end{one} has had its leading line break removed.

To understand it, let’s talk about how latexindent.pl has processed Listing 503; specifically latexindent.pl:

finds the environment named one
searches one for code blocks
1. finds the environment named two
2. searches two for code blocks, finds none
3. does the poly-switch work for two instructed by Listing 505: remove the line break before the end statement, and adds a line break after the end statement.
does the poly-switch work for one instructed by Listing 504 which is: remove line breaks before the end statement, and add a line break after the end statement;

Example 143

We can explore this further using the poly-switches in Listing 507; upon running the command

latexindent.pl -m -l=nested-env-mlb2.yaml nested-env.tex

we obtain the output given in Listing 506.

Listing 506 nested-env.tex using Listing 507

\begin{one}
	one text
	\begin{two}
		two text
	\end{two}
\end{one}

Listing 507 nested-env-mlb2.yaml

modifyLineBreaks:
    environments:
        EndStartsOnOwnLine: 1
        EndFinishesWithLineBreak: -1

To understand it, let’s talk about how latexindent.pl has processed Listing 506; specifically latexindent.pl:

finds the environment named one
searches one for code blocks
1. finds the environment named two
2. searches two for code blocks, finds none
3. does the poly-switch work for two instructed by Listing 505: add a line break before the end statement, and remove line breaks after the end statement.
does the poly-switch work for one instructed by Listing 507 which is: add a line break before the end statement, and remove line breaks after the end statement.

mlep. 2017. “One Sentence Per Line.” August 16, 2017. https://github.com/cmhughes/latexindent.pl/issues/81.

“Text::Wrap Perl Module.” n.d. Accessed May 1, 2017. http://perldoc.perl.org/Text/Wrap.html.

1: There is no longer any need for the code block to be specified within lookForAlignDelims for DBS poly-switches to activate.
2: LSqB stands for Left Square Bracket
3: LCuB stands for Left Curly Brace

4. The -m (modifylinebreaks) switch

4.1. Text Wrapping

4.1.1. Text wrap: overview

4.1.2. Text wrap: simple examples

4.1.3. Text wrap: blocksFollow examples

4.1.4. Text wrap: blocksBeginWith examples

4.1.5. Text wrap: blocksEndBefore examples

4.1.6. Text wrap: trailing comments and spaces

4.1.7. Text wrap: when before/after

4.1.8. Text wrap: wrapping comments

4.1.9. Text wrap: huge, tabstop and separator

4.2. oneSentencePerLine: modifying line breaks for sentences

4.2.1. oneSentencePerLine: overview

4.2.2. oneSentencePerLine: sentencesFollow

4.2.3. oneSentencePerLine: sentencesBeginWith

4.2.4. oneSentencePerLine: sentencesEndWith

4.2.5. oneSentencePerLine: sentencesDoNOTcontain

4.2.6. Features of the oneSentencePerLine routine

4.2.7. oneSentencePerLine: text wrapping and indenting sentences

4.2.8. oneSentencePerLine: text wrapping and indenting sentences, when before/after

4.2.9. oneSentencePerLine: text wrapping sentences and comments

4.3. Poly-switches

4.3.1. Poly-switches for environments

4.3.1.1. Adding line breaks: BeginStartsOnOwnLine and BodyStartsOnOwnLine

4.3.1.2. Adding line breaks: EndStartsOnOwnLine and EndFinishesWithLineBreak

4.3.1.3. poly-switches 1, 2, and 3 only add line breaks when necessary

4.3.1.4. Removing line breaks (poly-switches set to \(-1\))

4.3.1.5. About trailing horizontal space

4.3.1.6. poly-switch line break removal and blank lines

4.3.2. Poly-switches for double backslash

4.3.2.1. Double backslash starts on own line

4.3.2.2. Double backslash finishes with line break

4.3.2.3. Double backslash poly-switches for specialBeginEnd

4.3.2.4. Double backslash poly-switches for optional and mandatory arguments

4.3.2.5. Double backslash optional square brackets

4.3.3. Poly-switches for commas

4.3.3.1. Comma starts on own line

4.3.3.2. Comma finishes with line break

4.3.4. Poly-switches for other code blocks

4.3.5. Conflicting poly-switches: sequential code blocks

4.3.6. Conflicting poly-switches: nested code blocks

4.1.3. Text wrap: `blocksFollow` examples

4.1.4. Text wrap: `blocksBeginWith` examples

4.1.5. Text wrap: `blocksEndBefore` examples