perltidy - a perl script indenter and reformatter
perltidy [ options ] file1 file2 file3 ...
(output goes to file1.tdy, file2.tdy, file3.tdy, ...)
perltidy [ options ] file1 -o outfile
perltidy [ options ] file1 -st >outfile
perltidy [ options ] <infile >outfile
Perltidy reads a perl script and writes an indented, reformatted script.
Many users will find enough information in "EXAMPLES" to get started. New users may benefit from the short tutorial which can be found at http://perltidy.sourceforge.net/tutorial.html
A convenient aid to systematically defining a set of style parameters can be found at http://perltidy.sourceforge.net/stylekey.html
Perltidy can produce output on either of two modes, depending on the existence of an -html flag. Without this flag, the output is passed through a formatter. The default formatting tries to follow the recommendations in perlstyle(1), but it can be controlled in detail with numerous input parameters, which are described in "FORMATTING OPTIONS".
When the -html flag is given, the output is passed through an HTML formatter which is described in "HTML OPTIONS".
perltidy somefile.pl
This will produce a file somefile.pl.tdy containing the script reformatted using the default options, which approximate the style suggested in perlstyle(1). Perltidy never changes the input file.
perltidy *.pl
Execute perltidy on all .pl files in the current directory with the default options. The output will be in files with an appended .tdy extension. For any file with an error, there will be a file with extension .ERR.
perltidy -b file1.pl file2.pl
Modify file1.pl and file1.pl in place, and backup the originals to file1.pl.bak and file2.pl.bak. If file1.pl.bak and/or file2.pl.bak already exist, they will be overwritten.
perltidy -gnu somefile.pl
Execute perltidy on file somefile.pl with a style which approximates the GNU Coding Standards for C programs. The output will be somefile.pl.tdy.
perltidy -i=3 somefile.pl
Execute perltidy on file somefile.pl, with 3 columns for each level of indentation (-i=3) instead of the default 4 columns. There will not be any tabs in the reformatted script, except for any which already exist in comments, pod documents, quotes, and here documents. Output will be somefile.pl.tdy.
perltidy -i=3 -et=8 somefile.pl
Same as the previous example, except that leading whitespace will be entabbed with one tab character per 8 spaces.
perltidy -ce -l=72 somefile.pl
Execute perltidy on file somefile.pl with all defaults except use "cuddled elses" (-ce) and a maximum line length of 72 columns (-l=72) instead of the default 80 columns.
perltidy -g somefile.pl
Execute perltidy on file somefile.pl and save a log file somefile.pl.LOG which shows the nesting of braces, parentheses, and square brackets at the start of every line.
perltidy -html somefile.pl
This will produce a file somefile.pl.html containing the script with html markup. The output file will contain an embedded style sheet in the <HEAD> section which may be edited to change the appearance.
perltidy -html -css=mystyle.css somefile.pl
This will produce a file somefile.pl.html containing the script with html markup. This output file will contain a link to a separate style sheet file mystyle.css. If the file mystyle.css does not exist, it will be created. If it exists, it will not be overwritten.
perltidy -html -pre somefile.pl
Write an html snippet with only the PRE section to somefile.pl.html. This is useful when code snippets are being formatted for inclusion in a larger web page. No style sheet will be written in this case.
perltidy -html -ss >mystyle.css
Write a style sheet to mystyle.css and exit.
perltidy -html -frm mymodule.pm
Write html with a frame holding a table of contents and the source code. The output files will be mymodule.pm.html (the frame), mymodule.pm.toc.html (the table of contents), and mymodule.pm.src.html (the source code).
The entire command line is scanned for options, and they are processed before any files are processed. As a result, it does not matter whether flags are before or after any filenames. However, the relative order of parameters is important, with later parameters overriding the values of earlier parameters.
For each parameter, there is a long name and a short name. The short names are convenient for keyboard input, while the long names are self-documenting and therefore useful in scripts. It is customary to use two leading dashes for long names, but one may be used.
Most parameters which serve as on/off flags can be negated with a leading "n" (for the short name) or a leading "no" or "no-" (for the long name). For example, the flag to outdent long quotes is is -olq or --outdent-long-quotes. The flag to skip this is -nolq or --nooutdent-long-quotes or --no-outdent-long-quotes.
Options may not be bundled together. In other words, options -q and -g may NOT be entered as -qg.
Option names may be terminated early as long as they are uniquely identified. For example, instead of --dump-token-types, it would be sufficient to enter --dump-tok, or even --dump-t, to uniquely identify this command.
The following parameters concern the files which are read and written.
Perltidy must be able to operate on an arbitrarily large number of files in a single run, with each output being directed to a different output file. Obviously this would conflict with outputting to the single standard output device, so a special flag, -st, is required to request outputting to the standard output. For example,
perltidy somefile.pl -st >somefile.new.pl
This option may only be used if there is just a single input file. The default is -nst or --nostandard-output.
When perltidy creates a filename for an output file, by default it merely appends an extension to the path and basename of the input file. This parameter causes the path to be changed to path instead.
The path should end in a valid path separator character, but perltidy will try to add one if it is missing.
For example
perltidy somefile.pl -opath=/tmp/
will produce /tmp/somefile.pl.tdy. Otherwise, somefile.pl.tdy will appear in whatever directory contains somefile.pl.
If the path contains spaces, it should be placed in quotes.
This parameter will be ignored if output is being directed to standard output, or if it is being specified explicitly with the -o=s parameter.
Modify the input file or files in-place and save the original with the extension .bak. Any existing .bak file will be deleted. See next item for changing the default backup extension.
A -b flag will be ignored if input is from standard input, or if the -html flag is set.
Deactivate error messages and syntax checking (for running under an editor).
For example, if you use a vi-style editor, such as vim, you may execute perltidy as a filter from within the editor using something like
:n1,n2!perltidy -q
where n1,n2 represents the selected text. Without the -q flag,
any error message may mess up your screen, so be prepared to use your
"undo" key.
Set maximum interval between input code lines in the logfile. This purpose of
this flag is to assist in debugging nesting errors. The value of n is
optional. If you set the flag -g without the value of n, it will be
taken to be 1, meaning that every line will be written to the log file. This
can be helpful if you are looking for a brace, paren, or bracket nesting error.
Setting -g also causes the logfile to be saved, so it is not necessary to also include -log.
If no -g flag is given, a value of 50 will be used, meaning that at least every 50th line will be recorded in the logfile. This helps prevent excessively long log files.
Setting a negative value of n is the same as not setting -g at all.
Ignore any .perltidyrc command file. Normally, perltidy looks first in your current directory for a .perltidyrc file of parameters. (The format is described below). If it finds one, it applies those options to the initial default values, and then it applies any that have been defined on the command line. If no .perltidyrc file is found, it looks for one in your home directory.
If you set the -npro flag, perltidy will not look for this file.
To simplify testing and switching .perltidyrc files, this command may be used to specify a configuration file which will override the default name of .perltidyrc. There must not be a space on either side of the '=' sign. For example, the line
perltidy -pro=testcfg
would cause file testcfg to be used instead of the default .perltidyrc.
Using tab characters will almost certainly lead to future portability and maintenance problems, so the default and recommendation is not to use them. For those who prefer tabs, however, there are two different options.
Except for possibly introducing tab indentation characters, as outlined below, perltidy does not introduce any tab characters into your file, and it removes any tabs from the code (unless requested not to do so with -fws). If you have any tabs in your comments, quotes, or here-documents, they will remain.
This flag causes perltidy to run perl -c -T to check syntax of input
and output. (To change the flags passed to perl, see the next
item, -pscf). The results are written to the .LOG file, which
will be saved if an error is detected in the output script. The output
script is not checked if the input script has a syntax error. Perltidy
does its own checking, but this option employs perl to get a "second
opinion".
If perl reports errors in the input file, they will not be reported in the error output unless the --warning-output flag is given.
The default is not to do this type of syntax checking (although perltidy will still do as much self-checking as possible). The reason is that it causes all code in BEGIN blocks to be executed, for all modules being used, and this opens the door to security issues and infinite loops when running perltidy.
When perl is invoked to check syntax, the normal flags are -c -T. In
addition, if the -x flag is given to perltidy, then perl will also be
passed a -x flag. It should not normally be necessary to change
these flags, but it can be done with the -pscf=s flag. For example,
if the taint flag, -T, is not wanted, the flag could be set to be just
-pscf=-c.
Perltidy will pass your string to perl with the exception that it will add a -c and -x if appropriate. The .LOG file will show exactly what flags were passed to perl.
This flag is used to deactivate all formatting and line break changes. When it is in effect, the only change to the script will be indentation. And any flags controlling whitespace and newlines will be ignored. You might want to use this if you are perfectly happy with your whitespace and line breaks, and merely want perltidy to handle the indentation. (This also speeds up perltidy by well over a factor of two, so it might be useful when perltidy is merely being used to help find a brace error in a large script).
Setting this flag is equivalent to setting --freeze-newlines and --freeze-whitespace.
win, dos, unix, or mac. This flag tells perltidy
to output line endings for a specific system. Normally,
perltidy writes files with the line separator character of the host
system. The win and dos flags have an identical result.
Continuation indentation is extra indentation spaces applied when a long line is broken. The default is n=2, illustrated here:
my $level = # -ci=2 ( $max_index_to_go >= 0 ) ? $levels_to_go[0] : $last_output_level;
The same example, with n=0, is a little harder to read:
my $level = # -ci=0 ( $max_index_to_go >= 0 ) ? $levels_to_go[0] : $last_output_level;
The value given to -ci is also used by some commands when a small space is required. Examples are commands for outdenting labels, -ola, and control keywords, -okw.
When default values are not used, it is suggested that the value n given with -ci=n be no more than about one-half of the number of spaces assigned to a full indentation level on the -i=n command.
By default, perltidy indents lists with 4 spaces, or whatever value is specified with -i=n. Here is a small list formatted in this way:
# perltidy (default)
@month_of_year = (
'Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun',
'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'
);
Use the -lp flag to add extra indentation to cause the data to begin past the opening parentheses of a sub call or list, or opening square bracket of an anonymous array, or opening curly brace of an anonymous hash. With this option, the above list would become:
# perltidy -lp
@month_of_year = (
'Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun',
'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'
);
If the available line length (see -l=n ) does not permit this much space, perltidy will use less. For alternate placement of the closing paren, see the next section.
This option has no effect on code BLOCKS, such as if/then/else blocks, which always use whatever is specified with -i=n. Also, the existence of line breaks and/or block comments between the opening and closing parens may cause perltidy to temporarily revert to its default method.
Note: The -lp option may not be used together with the -t tabs option. It may, however, be used with the -et=n tab method.
In addition, any parameter which significantly restricts the ability of perltidy to choose newlines will conflict with -lp and will cause -lp to be deactivated. These include -io, -fnl, -nanl, and -ndnl. The reason is that the -lp indentation style can require the careful coordination of an arbitrary number of break points in hierarchical lists, and these flags may prevent that.
The -cti=n flag controls the indentation of a line beginning with
a ), ], or a non-block }. Such a line receives:
-cti = 0 no extra indentation (default)
-cti = 1 extra indentation such that the closing token
aligns with its opening token.
-cti = 2 one extra indentation level if the line looks like:
); or ]; or };
-cti = 3 one extra indentation level always
The flags -cti=1 and -cti=2 work well with the -lp flag (previous section).
# perltidy -lp -cti=1
@month_of_year = (
'Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun',
'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'
);
# perltidy -lp -cti=2
@month_of_year = (
'Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun',
'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'
);
These flags are merely hints to the formatter and they may not always be followed. In particular, if -lp is not being used, the indentation for cti=1 is constrained to be no more than one indentation level.
If desired, this control can be applied independently to each of the closing container token types. In fact, -cti=n is merely an abbreviation for -cpi=n -csbi=n -cbi=n, where: -cpi or --closing-paren-indentation controls )'s, -csbi or --closing-square-bracket-indentation controls ]'s, -cbi or --closing-brace-indentation controls non-block }'s.
The -icb option gives one extra level of indentation to a brace which terminates a code block . For example,
if ($task) {
yyy();
} # -icb
else {
zzz();
}
The default is not to do this, indicated by -nicb.
This command will cause labels to be outdented by 2 spaces (or whatever -ci has been set to), if possible. This is the default. For example:
my $i;
LOOP: while ( $i = <FOTOS> ) {
chomp($i);
next unless $i;
fixit($i);
}
Use -nola to not outdent labels.
The command -okw will will cause certain leading control keywords to
be outdented by 2 spaces (or whatever -ci has been set to), if
possible. By default, these keywords are redo, next, last,
goto, and return. The intention is to make these control keywords
easier to see. To change this list of keywords being outdented, see
the next section.
For example, using perltidy -okw on the previous example gives:
my $i;
LOOP: while ( $i = <FOTOS> ) {
chomp($i);
next unless $i;
fixit($i);
}
The default is not to do this.
This command can be used to change the keywords which are outdented with the -okw command. The parameter string is a required list of perl keywords, which should be placed in quotes if there are more than one. By itself, it does not cause any outdenting to occur, so the -okw command is still required.
For example, the commands -okwl="next last redo goto" -okw will cause
those four keywords to be outdented. It is probably simplest to place
any -okwl command in a .perltidyrc file.
Whitespace refers to the blank space between variables, operators, and other code tokens.
Here the term "tightness" will mean the closeness with which
pairs of enclosing tokens, such as parentheses, contain the quantities
within. A numerical value of 0, 1, or 2 defines the tightness, with
0 being least tight and 2 being most tight. Spaces within containers
are always symmetric, so if there is a space after a ( then there
will be a space before the corresponding ).
The -pt=n or --paren-tightness=n parameter controls the space within parens. The example below shows the effect of the three possible values, 0, 1, and 2:
if ( ( my $len_tab = length( $tabstr ) ) > 0 ) { # -pt=0
if ( ( my $len_tab = length($tabstr) ) > 0 ) { # -pt=1 (default)
if ((my $len_tab = length($tabstr)) > 0) { # -pt=2
When n is 0, there is always a space to the right of a '(' and to the left of a ')'. For n=2 there is never a space. For n=1, the default, there is a space unless the quantity within the parens is a single token, such as an identifier or quoted string.
Likewise, the parameter -sbt=n or --square-bracket-tightness=n controls the space within square brackets, as illustrated below.
$width = $col[ $j + $k ] - $col[ $j ]; # -sbt=0 $width = $col[ $j + $k ] - $col[$j]; # -sbt=1 (default) $width = $col[$j + $k] - $col[$j]; # -sbt=2
Curly braces which do not contain code blocks are controlled by the parameter -bt=n or --brace-tightness=n.
$obj->{ $parsed_sql->{ 'table' }[0] }; # -bt=0
$obj->{ $parsed_sql->{'table'}[0] }; # -bt=1 (default)
$obj->{$parsed_sql->{'table'}[0]}; # -bt=2
And finally, curly braces which contain blocks of code are controlled by the parameter -bbt=n or --block-brace-tightness=n as illustrated in the example below.
%bf = map { $_ => -M $_ } grep { /\.deb$/ } dirents '.'; # -bbt=0 (default)
%bf = map { $_ => -M $_ } grep {/\.deb$/} dirents '.'; # -bbt=1
%bf = map {$_ => -M $_} grep {/\.deb$/} dirents '.'; # -bbt=2
Some programmers prefer a space before all terminal semicolons. The default is for no such space, and is indicated with -nsts or --nospace-terminal-semicolon.
$i = 1 ; # -sts $i = 1; # -nsts (default)
Semicolons within for loops may sometimes be hard to see, particularly when commas are also present. This option places spaces on both sides of these special semicolons, and is the default. Use -nsfs or --nospace-for-semicolon to deactivate it.
for ( @a = @$ap, $u = shift @a ; @a ; $u = $v ) { # -sfs (default)
for ( @a = @$ap, $u = shift @a; @a; $u = $v ) { # -nsfs
For those who want more detailed control over the whitespace around tokens, there are four parameters which can directly modify the default whitespace rules built into perltidy for any token. They are:
-wls=s or --want-left-space=s,
-nwls=s or --nowant-left-space=s,
-wrs=s or --want-right-space=s,
-nwrs=s or --nowant-right-space=s.
These parameters are each followed by a quoted string, s, containing a list of token types. No more than one of each of these parameters should be specified, because repeating a command-line parameter always overwrites the previous one before perltidy ever sees it.
To illustrate how these are used, suppose it is desired that there be no space on either side of the token types = + - / *. The following two parameters would specify this desire:
-nwls="= + - / *" -nwrs="= + - / *"
(Note that the token types are in quotes, and that they are separated by spaces). With these modified whitespace rules, the following line of math:
$root = -$b + sqrt( $b * $b - 4. * $a * $c ) / ( 2. * $a );
becomes this:
$root=-$b+sqrt( $b*$b-4.*$a*$c )/( 2.*$a );
These parameters should be considered to be hints to perltidy rather than fixed rules, because perltidy must try to resolve conflicts that arise between them and all of the other rules that it uses. One conflict that can arise is if, between two tokens, the left token wants a space and the right one doesn't. In this case, the token not wanting a space takes priority.
It is necessary to have a list of all token types in order to create this type of input. Such a list can be obtained by the command --dump-token-types. Also try the -D flag on a short snippet of code and look at the .DEBUG file to see the tokenization.
WARNING Be sure to put these tokens in quotes to avoid having them misinterpreted by your command shell.
When an opening paren follows a Perl keyword, no space is introduced after the keyword, unless it is (by default) one of these:
my local our and or eq ne if else elsif until unless while for foreach return switch case given when
These defaults can be modified with two commands:
-sak=s or --space-after-keyword=s adds keywords.
-nsak=s or --nospace-after-keyword=s removes keywords.
where s is a list of keywords (in quotes if necessary). For example,
my ( $a, $b, $c ) = @_; # default my( $a, $b, $c ) = @_; # -nsak="my local our"
To put a space after all keywords, see the next item.
When an opening paren follows a function or keyword, no space is introduced after the keyword except for the keywords noted in the previous item. To always put a space between a function or keyword and its opening paren, use the command:
-skp or --space-keyword-paren
You will probably also want to use the flag -sfp (next item) too.
When an opening paren follows a function the default is not to introduce a space. To cause a space to be introduced use:
-sfp or --space-function-paren
myfunc( $a, $b, $c ); # default myfunc ( $a, $b, $c ); # -sfp
You will probably also want to use the flag -skp (previous item) too.
qw quotes
-tqw or --trim-qw provide the default behavior of trimming
spaces around multi-line qw quotes and indenting them appropriately.
-ntqw or --notrim-qw cause leading and trailing whitespace around
multi-line qw quotes to be left unchanged. This option will not
normally be necessary, but was added for testing purposes, because in
some versions of perl, trimming qw quotes changes the syntax tree.
Perltidy has a number of ways to control the appearance of both block comments and side comments. The term block comment here refers to a full-line comment, whereas side comment will refer to a comment which appears on a line to the right of some code.
Block comments normally look best when they are indented to the same level as the code which follows them. This is the default behavior, but you may use -nibc to keep block comments left-justified. Here is an example:
# this comment is indented (-ibc, default)
if ($task) { yyy(); }
The alternative is -nibc:
# this comment is not indented (-nibc)
if ($task) { yyy(); }
See also the next item, -isbc, as well as -sbc, for other ways to have some indented and some outdented block comments.
If there is no leading space on the line, then the comment will not be indented, and otherwise it may be.
If both -ibc and -isbc are set, then -isbc takes priority.
By default, perltidy tries to identify and align "hanging side comments", which are something like this:
my $IGNORE = 0; # This is a side comment
# This is a hanging side comment
# And so is this
A comment is considered to be a hanging side comment if (1) it immediately follows a line with a side comment, or another hanging side comment, and (2) there is some leading whitespace on the line. To deactivate this feature, use -nhsc or --nohanging-side-comments. If block comments are preceded by a blank line, or have no leading whitespace, they will not be mistaken as hanging side comments.
A closing side comment is a special comment which perltidy can automatically create and place after the closing brace of a code block. They can be useful for code maintenance and debugging. The command -csc (or --closing-side-comments) adds or updates closing side comments. For example, here is a small code snippet
sub message {
if ( !defined( $_[0] ) ) {
print("Hello, World\n");
}
else {
print( $_[0], "\n" );
}
}
And here is the result of processing with perltidy -csc:
sub message {
if ( !defined( $_[0] ) ) {
print("Hello, World\n");
}
else {
print( $_[0], "\n" );
}
} ## end sub message
A closing side comment was added for sub message in this case, but not
for the if and else blocks, because they were below the 6 line
cutoff limit for adding closing side comments. This limit may be
changed with the -csci command, described below.
The command -dcsc (or --delete-closing-side-comments) reverses this process and removes these comments.
Several commands are available to modify the behavior of these two basic commands, -csc and -dcsc:
where n is the minimum number of lines that a block must have in
order for a closing side comment to be added. The default value is
n=6. To illustrate:
# perltidy -csci=2 -csc
sub message {
if ( !defined( $_[0] ) ) {
print("Hello, World\n");
} ## end if ( !defined( $_[0] ))
else {
print( $_[0], "\n" );
} ## end else [ if ( !defined( $_[0] ))
} ## end sub message
Now the if and else blocks are commented. However, now this has
become very cluttered.
## end. This string will be added to
closing side comments, and it will also be used to recognize them in
order to update, delete, and format them. Any comment identified as a
closing side comment will be placed just a single space to the right of
its closing brace.
where string is a list of block types to be tagged with closing side
comments. By default, all code block types preceded by a keyword or
label (such as if, sub, and so on) will be tagged. The -cscl
command changes the default list to be any selected block types; see
Specifying Block Types.
For example, the following command
requests that only sub's, labels, BEGIN, and END blocks be
affected by any -csc or -dcsc operation:
-cscl="sub : BEGIN END"
if block, is
whatever lies between the keyword introducing the block, such as if,
and the opening brace. Since this might be too much text for a side
comment, there needs to be a limit, and that is the purpose of this
parameter. The default value is n=20, meaning that no additional
tokens will be appended to this text after its length reaches 20
characters. Omitted text is indicated with .... (Tokens, including
sub names, are never truncated, however, so actual lengths may exceed
this). To illustrate, in the above example, the appended text of the
first block is ( !defined( $_[0] ).... The existing limit of
n=20 caused this text to be truncated, as indicated by the ....
The default, n=0, places the text of the opening if statement after any
terminal else.
If n=2 is used, then each elsif is also given the text of the opening
if statement. Also, an else will include the text of a preceding
elsif statement. Note that this may result some long closing
side comments.
If n=1 is used, the results will be the same as n=2 whenever the resulting line length is less than the maximum allowed.
This parameter is intended to help make the initial transition to the use of closing side comments. It causes two things to happen if a closing side comment replaces an existing, different closing side comment: first, an error message will be issued, and second, the original side comment will be placed alone on a new specially marked comment line for later attention.
The intent is to avoid clobbering existing hand-written side comments which happen to match the pattern of closing side comments. This flag should only be needed on the first run with -csc.
Important Notes on Closing Side Comments:
## end to be ## End, since the test is
case sensitive. You may also want to use the -ssc flag to keep these
modified closing side comments spaced the same as actual closing side comments.
Static block comments are block comments with a special leading pattern,
## by default, which will be treated slightly differently from other
block comments. They effectively behave as if they had glue along their
left and top edges, because they stick to the left edge and previous line
when there is no blank spaces in those places. This option is
particularly useful for controlling how commented code is displayed.
When -sbc is used, a block comment with a special leading pattern, ## by
default, will be treated specially.
Comments so identified are treated as follows:
For example, assuming @month_of_year is
left-adjusted:
@month_of_year = ( # -sbc (default)
'Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct',
## 'Dec', 'Nov'
'Nov', 'Dec');
Without this convention, the above code would become
@month_of_year = ( # -nsbc
'Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct',
## 'Dec', 'Nov'
'Nov', 'Dec'
);
which is not as clear. The default is to use -sbc. This may be deactivated with -nsbc.
This parameter defines the prefix used to identify static block comments
when the -sbc parameter is set. The default prefix is ##,
corresponding to -sbcp=##. The prefix is actually part of a perl
pattern used to match lines and it must either begin with # or ^#.
In the first case a prefix ^\s* will be added to match any leading
whitespace, while in the second case the pattern will match only
comments with no leading whitespace. For example, to
identify all comments as static block comments, one would use -sbcp=#.
To identify all left-adjusted comments as static block comments, use -sbcp='^#'.
Please note that -sbcp merely defines the pattern used to identify static block comments; it will not be used unless the switch -sbc is set. Also, please be aware that since this string is used in a perl regular expression which identifies these comments, it must enable a valid regular expression to be formed.
A pattern which can be useful is:
-sbcp=^#{2,}[^\s#]
This pattern requires a static block comment to have at least one character which is neither a # nor a space. It allows a line containing only '#' characters to be rejected as a static block comment. Such lines are often used at the start and end of header information in subroutines and should not be separated from the intervening comments, which typically begin with just a single '#'.
Static side comments are side comments with a special leading pattern. This option can be useful for controlling how commented code is displayed when it is a side comment.
When -ssc is used, a side comment with a static leading pattern, which is
## by default, will be be spaced only a single space from previous
character, and it will not be vertically aligned with other side comments.
The default is -nssc.
This parameter defines the prefix used to identify static side comments
when the -ssc parameter is set. The default prefix is ##,
corresponding to -sscp=##.
Please note that -sscp merely defines the pattern used to identify static side comments; it will not be used unless the switch -ssc is set. Also, note that this string is used in a perl regular expression which identifies these comments, so it must enable a valid regular expression to be formed.
Selected lines of code may be passed verbatim to the output without any formatting. This feature is enabled by default but can be disabled with the --noformat-skipping or -nfs flag. It should be used sparingly to avoid littering code with markers, but it might be helpful for working around occasional problems. For example it might be useful for keeping the indentation of old commented code unchanged, keeping indentation of long blocks of aligned comments unchanged, keeping certain list formatting unchanged, or working around a glitch in perltidy.
This flag, which is enabled by default, causes any code between special beginning and ending comment markers to be passed to the output without formatting. The default beginning marker is #<<< and the default ending marker is #>>> but they may be changed (see next items below). Additional text may appear on these special comment lines provided that it is separated from the marker by at least one space. For example
#<<< do not let perltidy touch this
my @list = (1,
1, 1,
1, 2, 1,
1, 3, 3, 1,
1, 4, 6, 4, 1,);
#>>>
The comment markers may be placed at any location that a block comment may appear. If they do not appear to be working, use the -log flag and examine the .LOG file. Use -nfs to disable this feature.
The -fsb=string parameter may be used to change the beginning marker for format skipping. The default is equivalent to -fsb='#<<<'. The string that you enter must begin with a # and should be in quotes as necessary to get past the command shell of your system. It is actually the leading text of a pattern that is constructed by appending a '\s', so you must also include backslashes for characters to be taken literally rather than as patterns.
Some examples show how example strings become patterns:
-fsb='#\{\{\{' becomes /^#\{\{\{\s/ which matches #{{{ but not #{{{{
-fsb='#\*\*' becomes /^#\*\*\s/ which matches #** but not #***
-fsb='#\*{2,}' becomes /^#\*{2,}\s/ which matches #** and #*****
Enable the "cuddled else" style, in which else and elsif are
follow immediately after the curly brace closing the previous block.
The default is not to use cuddled elses, and is indicated with the flag
-nce or --nocuddled-else. Here is a comparison of the
alternatives:
if ($task) {
yyy();
} else { # -ce
zzz();
}
if ($task) {
yyy();
}
else { # -nce (default)
zzz();
}
Use the flag -bl to place the opening brace on a new line:
if ( $input_file eq '-' ) # -bl
{
important_function();
}
This flag applies to all structural blocks, including sub's (unless the -sbl flag is set -- see next item).
The default style, -nbl, places an opening brace on the same line as the keyword introducing it. For example,
if ( $input_file eq '-' ) { # -nbl (default)
The flag -sbl can be used to override the value of -bl for opening sub braces. For example,
perltidy -sbl
produces this result:
sub message
{
if (!defined($_[0])) {
print("Hello, World\n");
}
else {
print($_[0], "\n");
}
}
This flag is negated with -nsbl. If -sbl is not specified, the value of -bl is used.
The flag -bli is the same as -bl but in addition it causes one unit of continuation indentation ( see -ci ) to be placed before an opening and closing block braces.
For example,
if ( $input_file eq '-' ) # -bli
{
important_function();
}
By default, this extra indentation occurs for blocks of type: if, elsif, else, unless, for, foreach, sub, while, until, and also with a preceding label. The next item shows how to change this.
if/elsif/else blocks.
The default style, -nbl places the opening code block brace on a new line if it does not fit on the same line as the opening keyword, like this:
if ( $bigwasteofspace1 && $bigwasteofspace2
|| $bigwasteofspace3 && $bigwasteofspace4 )
{
big_waste_of_time();
}
To force the opening brace to always be on the right, use the -bar flag. In this case, the above example becomes
if ( $bigwasteofspace1 && $bigwasteofspace2
|| $bigwasteofspace3 && $bigwasteofspace4 ) {
big_waste_of_time();
}
A conflict occurs if both -bl and -bar are specified.
The -otr flag is a hint that perltidy should not place a break between a comma and an opening token. For example:
# default formatting
push @{ $self->{$module}{$key} },
{
accno => $ref->{accno},
description => $ref->{description}
};
# perltidy -otr
push @{ $self->{$module}{$key} }, {
accno => $ref->{accno},
description => $ref->{description}
};
The flag -otr is actually a synonym for three other flags which can be used to control parens, hash braces, and square brackets separately if desired:
-opr or --opening-paren-right -ohbr or --opening-hash-brace-right -osbr or --opening-square-bracket-right
These parameters control what shall be called vertical tightness. Here are the main points:
Opening tokens (except for block braces) are controlled by -vt=n, or --vertical-tightness=n, where
-vt=0 always break a line after opening token (default).
-vt=1 do not break unless this would produce more than one
step in indentation in a line.
-vt=2 never break a line after opening token
Closing tokens (except for block braces) are controlled by -vtc=n, or --vertical-tightness-closing=n, where
-vtc=0 always break a line before a closing token (default),
-vtc=1 do not break before a closing token which is followed
by a semicolon or another closing token, and is not in
a list environment.
-vtc=2 never break before a closing token.
The rules for -vtc=1 are designed to maintain a reasonable balance between tightness and readability in complex lists.
Here are some examples:
# perltidy -lp -vt=0 -vtc=0
%romanNumerals = (
one => 'I',
two => 'II',
three => 'III',
four => 'IV',
);
# perltidy -lp -vt=1 -vtc=0
%romanNumerals = ( one => 'I',
two => 'II',
three => 'III',
four => 'IV',
);
# perltidy -lp -vt=1 -vtc=1
%romanNumerals = ( one => 'I',
two => 'II',
three => 'III',
four => 'IV', );
The difference between -vt=1 and -vt=2 is shown here:
# perltidy -lp -vt=1
$init->add(
mysprintf( "(void)find_threadsv(%s);",
cstring( $threadsv_names[ $op->targ ] )
)
);
# perltidy -lp -vt=2
$init->add( mysprintf( "(void)find_threadsv(%s);",
cstring( $threadsv_names[ $op->targ ] )
)
);
With -vt=1, the line ending in add( does not combine with the next
line because the next line is not balanced. This can help with
readability, but -vt=2 can be used to ignore this rule.
The tightest, and least readable, code is produced with both -vt=2 and
-vtc=2:
# perltidy -lp -vt=2 -vtc=2
$init->add( mysprintf( "(void)find_threadsv(%s);",
cstring( $threadsv_names[ $op->targ ] ) ) );
Notice how the code in all of these examples collapses vertically as -vt increases, but the indentation remains unchanged. This is because perltidy implements the -vt parameter by first formatting as if -vt=0, and then simply overwriting one output line on top of the next, if possible, to achieve the desired vertical tightness. The -lp indentation style has been designed to allow this vertical collapse to occur, which is why it is required for the -vt parameter.
The -vt=n and -vtc=n parameters apply to each type of container token. If desired, vertical tightness controls can be applied independently to each of the closing container token types.
The parameters for controlling parentheses are -pvt=n or --paren-vertical-tightness=n, and -pcvt=n or --paren-vertical-tightness-closing=n.
Likewise, the parameters for square brackets are -sbvt=n or --square-bracket-vertical-tightness=n, and -sbcvt=n or --square-bracket-vertical-tightness-closing=n.
Finally, the parameters for controlling non-code block braces are -bvt=n or --brace-vertical-tightness=n, and -bcvt=n or --brace-vertical-tightness-closing=n.
In fact, the parameter -vt=n is actually just an abbreviation for -pvt=n -bvt=n sbvt=n, and likewise -vtc=n is an abbreviation for -pvtc=n -bvtc=n sbvtc=n.
The -bbvt=n flag is just like the -vt=n flag but applies to opening code block braces.
-bbvt=0 break after opening block brace (default).
-bbvt=1 do not break unless this would produce more than one
step in indentation in a line.
-bbvt=2 do not break after opening block brace.
It is necessary to also use either -bl or -bli for this to work, because, as with other vertical tightness controls, it is implemented by simply overwriting a line ending with an opening block brace with the subsequent line. For example:
# perltidy -bli -bbvt=0
if ( open( FILE, "< $File" ) )
{
while ( $File = <FILE> )
{
$In .= $File;
$count++;
}
close(FILE);
}
# perltidy -bli -bbvt=1
if ( open( FILE, "< $File" ) )
{ while ( $File = <FILE> )
{ $In .= $File;
$count++;
}
close(FILE);
}
By default this applies to blocks associated with keywords if, elsif, else, unless, for, foreach, sub, while, until, and also with a preceding label. This can be changed with the parameter -bbvtl=string, or --block-brace-vertical-tightness-list=string, where string is a space-separated list of block types. For more information on the possible values of this string, see Specifying Block Types
For example, if we want to just apply this style to if,
elsif, and else blocks, we could use
perltidy -bli -bbvt=1 -bbvtl='if elsif else'.
There is no vertical tightness control for closing block braces; with the exception of one-line blocks, they will normally remain on a separate line.
The -sot flag tells perltidy to "stack" opening tokens when possible to avoid lines with isolated opening tokens.
For example:
# default
$opt_c = Text::CSV_XS->new(
{
binary => 1,
sep_char => $opt_c,
always_quote => 1,
}
);
# -sot
$opt_c = Text::CSV_XS->new( {
binary => 1,
sep_char => $opt_c,
always_quote => 1,
}
);
For detailed control of individual closing tokens the following controls can be used:
-sop or --stack-opening-paren -sohb or --stack-opening-hash-brace -sosb or --stack-opening-square-bracket
The flag -sot is a synonym for -sop -sohb -sosb.
The -sct flag tells perltidy to "stack" closing tokens when possible to avoid lines with isolated closing tokens.
For example:
# default
$opt_c = Text::CSV_XS->new(
{
binary => 1,
sep_char => $opt_c,
always_quote => 1,
}
);
# -sct
$opt_c = Text::CSV_XS->new(
{
binary => 1,
sep_char => $opt_c,
always_quote => 1,
} );
The -sct flag is somewhat similar to the -vtc flags, and in some cases it can give a similar result. The difference is that the -vtc flags try to avoid lines with leading opening tokens by "hiding" them at the end of a previous line, whereas the -sct flag merely tries to reduce the number of lines with isolated closing tokens by stacking them but does not try to hide them. For example:
# -vtc=2
$opt_c = Text::CSV_XS->new(
{
binary => 1,
sep_char => $opt_c,
always_quote => 1, } );
For detailed control of the stacking of individual closing tokens the following controls can be used:
-scp or --stack-closing-paren -schb or --stack-closing-hash-brace -scsb or --stack-closing-square-bracket
The flag -sct is a synonym for -scp -schb -scsb.
By default, perltidy will add line breaks when necessary to create continuations of long lines and to improve the script appearance. Use -nanl or --noadd-newlines to prevent any new line breaks.
This flag does not prevent perltidy from eliminating existing line breaks; see --freeze-newlines to completely prevent changes to line break points.
Four command line parameters provide some control over whether a line break should be before or after specific token types. Two parameters give detailed control:
-wba=s or --want-break-after=s, and
-wbb=s or --want-break-before=s.
These parameters are each followed by a quoted string, s, containing a list of token types (separated only by spaces). No more than one of each of these parameters should be specified, because repeating a command-line parameter always overwrites the previous one before perltidy ever sees it.
By default, perltidy breaks after these token types: % + - * / x != == >= <= =~ !~ < > | & = **= += *= &= <<= &&= -= /= |= >>= ||= //= .= %= ^= x=
And perltidy breaks before these token types by default: . << >> -> && || //
To illustrate, to cause a break after a concatenation operator, '.',
rather than before it, the command line would be
-wba="."
As another example, the following command would cause a break before
math operators '+', '-', '/', and '*':
-wbb="+ - / *"
These commands should work well for most of the token types that perltidy uses (use --dump-token-types for a list). Also try the -D flag on a short snippet of code and look at the .DEBUG file to see the tokenization. However, for a few token types there may be conflicts with hardwired logic which cause unexpected results. One example is curly braces, which should be controlled with the parameter bl provided for that purpose.
WARNING Be sure to put these tokens in quotes to avoid having them misinterpreted by your command shell.
Two additional parameters are available which, though they provide no further capability, can simplify input are:
-baao or --break-after-all-operators,
-bbao or --break-before-all-operators.
The -baao sets the default to be to break after all of the following operators:
% + - * / x != == >= <= =~ !~ < > | &
= **= += *= &= <<= &&= -= /= |= >>= ||= //= .= %= ^= x=
. : ? && || and or err xor
and the -bbao flag sets the default to break before all of these operators. These can be used to define an initial break preference which can be fine-tuned with the -wba and -wbb flags. For example, to break before all operators except an = one could use --bbao -wba='=' rather than listing every single perl operator except = on a -wbb flag.
Perltidy attempts to place comma-separated arrays of values in tables which look good. Its default algorithms usually work well, and they have been improving with each release, but several parameters are available to control list formatting.
This flag tells perltidy to try to break at all old commas. This is not the default. Normally, perltidy makes a best guess at list formatting, and seldom uses old comma breakpoints. Usually this works well, but consider:
my @list = (1,
1, 1,
1, 2, 1,
1, 3, 3, 1,
1, 4, 6, 4, 1,);
The default formatting will flatten this down to one line:
# perltidy (default)
my @list = ( 1, 1, 1, 1, 2, 1, 1, 3, 3, 1, 1, 4, 6, 4, 1, );
which hides the structure. Using -boc, plus additional flags to retain the original style, yields
# perltidy -boc -lp -pt=2 -vt=1 -vtc=1
my @list = (1,
1, 1,
1, 2, 1,
1, 3, 3, 1,
1, 4, 6, 4, 1,);
A disadvantage of this flag is that all tables in the file must already be nicely formatted. For another possibility see the -fs flag in Skipping Selected Sections of Code.
If the computed number of fields for any table exceeds n, then it will be reduced to n. The default value for n is a large number, 40. While this value should probably be left unchanged as a general rule, it might be used on a small section of code to force a list to have a particular number of fields per line, and then either the -boc flag could be used to retain this formatting, or a single comment could be introduced somewhere to freeze the formatting in future applications of perltidy.
# perltidy -mft=2
@month_of_year = (
'Jan', 'Feb',
'Mar', 'Apr',
'May', 'Jun',
'Jul', 'Aug',
'Sep', 'Oct',
'Nov', 'Dec'
);
A comma which follows a comma arrow, '=>', requires special consideration. In a long list, it is common to break at all such commas. This parameter can be used to control how perltidy breaks at these commas. (However, it will have no effect if old comma breaks are being forced because -boc is used). The possible values of n are:
n=0 break at all commas after =>
n=1 stable: break at all commas after => unless this would break
an existing one-line container (default)
n=2 break at all commas after =>, but try to form the maximum
maximum one-line container lengths
n=3 do not treat commas after => specially at all
For example, given the following single line, perltidy by default will not add any line breaks because it would break the existing one-line container:
bless { B => $B, Root => $Root } => $package;
Using -cab=0 will force a break after each comma-arrow item:
# perltidy -cab=0:
bless {
B => $B,
Root => $Root
} => $package;
If perltidy is subsequently run with this container broken, then by default it will break after each '=>' because the container is now broken. To reform a one-line container, the parameter -cab=2 would be needed.
The flag -cab=3 can be used to prevent these commas from being treated specially. In this case, an item such as "01" => 31 is treated as a single item in a table. The number of fields in this table will be determined by the same rules that are used for any other table. Here is an example.
# perltidy -cab=3
my %last_day = (
"01" => 31, "02" => 29, "03" => 31, "04" => 30,
"05" => 31, "06" => 30, "07" => 31, "08" => 31,
"09" => 30, "10" => 31, "11" => 30, "12" => 31
);
Several additional parameters are available for controlling the extent to which line breaks in the input script influence the output script. In most cases, the default parameter values are set so that, if a choice is possible, the output style follows the input style. For example, if a short logical container is broken in the input script, then the default behavior is for it to remain broken in the output script.
Most of the parameters in this section would only be required for a one-time conversion of a script from short container lengths to longer container lengths. The opposite effect, of converting long container lengths to shorter lengths, can be obtained by temporarily using a short maximum line length.
&&, ||, and,
or or, then the container will remain broken. Also, breaks
at internal keywords if and unless will normally be retained.
To prevent this, and thus form longer lines, use -nbol.
sort and <map>. This allows chains of these
operators to be displayed one per line. Use -nbok to prevent
retaining these breakpoints.
:,
then it will remain broken. To prevent this, and thereby
form longer lines, use -nbot.
Use the -kis flag to prevent breaking at a semicolon if there was no break there in the input file. Normally perltidy places a newline after each semicolon which terminates a statement unless several statements are contained within a one-line brace block. To illustrate, consider the following input lines:
dbmclose(%verb_delim); undef %verb_delim;
dbmclose(%expanded); undef %expanded;
The default is to break after each statement, giving
dbmclose(%verb_delim);
undef %verb_delim;
dbmclose(%expanded);
undef %expanded;
With perltidy -kis the multiple statements are retained:
dbmclose(%verb_delim); undef %verb_delim;
dbmclose(%expanded); undef %expanded;
The statements are still subject to the specified value of maximum-line-length and will be broken if this maximum is exceeed.
Blank lines can improve the readability of a script if they are carefully placed. Perltidy has several commands for controlling the insertion, retention, and removal of blank lines.
A blank line will be introduced before blocks of coding delimited by for, foreach, while, until, and if, unless, in the following circumstances:
This is the default. The intention of this option is to introduce some space within dense coding. This is negated with -nbbb or --noblanks-before-blocks.
A style refers to a convenient collection of existing parameters.
-gnu gives an approximation to the GNU Coding Standards (which do not apply to perl) as they are sometimes implemented. At present, this style overrides the default style with the following parameters:
-lp -bl -noll -pt=2 -bt=2 -sbt=2 -icp
-pbp is an abbreviation for the parameters in the book Perl Best Practices by Damian Conway:
-l=78 -i=4 -ci=4 -st -se -vt=2 -cti=0 -pt=1 -bt=1 -sbt=1 -bbt=1 -nsfs -nolq
-wbb="% + - * / x != == >= <= =~ !~ < > | & =
**= += *= &= <<= &&= -= /= |= >>= ||= //= .= %= ^= x="
Note that the -st and -se flags make perltidy act as a filter on one file only. These can be overridden with -nst and -nse if necessary.
Perltidy can selectively delete comments and/or pod documentation. The command -dac or --delete-all-comments will delete all comments and all pod documentation, leaving just code and any leading system control lines.
The command -dp or --delete-pod will remove all pod documentation (but not comments).
Two commands which remove comments (but not pod) are: -dbc or --delete-block-comments and -dsc or --delete-side-comments. (Hanging side comments will be deleted with block comments here.)
The negatives of these commands also work, and are the defaults. When block comments are deleted, any leading 'hash-bang' will be retained. Also, if the -x flag is used, any system commands before a leading hash-bang will be retained (even if they are in the form of comments).
When perltidy writes a formatted text file, it has the ability to also send selected text to a file with a .TEE extension. This text can include comments and pod documentation.
The command -tac or --tee-all-comments will write all comments and all pod documentation.
The command -tp or --tee-pod will write all pod documentation (but not comments).
The commands which write comments (but not pod) are: -tbc or --tee-block-comments and -tsc or --tee-side-comments. (Hanging side comments will be written with block comments here.)
The negatives of these commands also work, and are the defaults.
If you use perltidy frequently, you probably won't be happy until you create a .perltidyrc file to avoid typing commonly-used parameters. Perltidy will first look in your current directory for a command file named .perltidyrc. If it does not find one, it will continue looking for one in other standard locations.
These other locations are system-dependent, and may be displayed with
the command perltidy -dpro. Under Unix systems, it will first look
for an environment variable PERLTIDY. Then it will look for a
.perltidyrc file in the home directory, and then for a system-wide
file /usr/local/etc/perltidyrc, and then it will look for
/etc/perltidyrc. Note that these last two system-wide files do not
have a leading dot. Further system-dependent information will be found
in the INSTALL file distributed with perltidy.
This file is free format, and simply a list of parameters, just as they would be entered on a command line. Any number of lines may be used, with any number of parameters per line, although it may be easiest to read with one parameter per line. Blank lines are ignored, and text after a '#' is ignored to the end of a line.
Here is an example of a .perltidyrc file:
# This is a simple of a .perltidyrc configuration file # This implements a highly spaced style -se # errors to standard error output -w # show all warnings -bl # braces on new lines -pt=0 # parens not tight at all -bt=0 # braces not tight -sbt=0 # square brackets not tight
The parameters in the .perltidyrc file are installed first, so any parameters given on the command line will have priority over them.
To avoid confusion, perltidy ignores any command in the .perltidyrc file which would cause some kind of dump and an exit. These are:
-h -v -ddf -dln -dop -dsn -dtt -dwls -dwrs -ss
There are several options may be helpful in debugging a .perltidyrc file:
A very helpful command is --dump-profile or -dpro. It writes a list of all configuration filenames tested to standard output, and if a file is found, it dumps the content to standard output before exiting. So, to find out where perltidy looks for its configuration files, and which one if any it selects, just enter
perltidy -dpro
A special notation is available for use in a .perltidyrc file for creating an abbreviation for a group of options. This can be used to create a shorthand for one or more styles which are frequently, but not always, used. The notation is to group the options within curly braces which are preceded by the name of the alias (without leading dashes), like this:
newword {
-opt1
-opt2
}
where newword is the abbreviation, and opt1, etc, are existing parameters or other abbreviations. The main syntax requirement is that the new abbreviation must begin on a new line. Space before and after the curly braces is optional. For a specific example, the following line
airy {-bl -pt=0 -bt=0 -sbt=0}
could be placed in a .perltidyrc file, and then invoked at will with
perltidy -airy somefile.pl
(Either -airy or --airy may be used).
#!...perl ),
you must use the -x flag to tell perltidy not to parse and format any
lines before the "hash-bang" line. This option also invokes perl with a
-x flag when checking the syntax. This option was originally added to
allow perltidy to parse interactive VMS scripts, but it should be used
for any script which is normally invoked with perl -x.
The goal of perltidy is to improve the readability of files, but there are two commands which have the opposite effect, --mangle and --extrude. They are actually merely aliases for combinations of other parameters. Both of these strip all possible whitespace, but leave comments and pod documents, so that they are essentially reversible. The difference between these is that --mangle puts the fewest possible line breaks in a script while --extrude puts the maximum possible. Note that these options do not provided any meaningful obfuscation, because perltidy can be used to reformat the files. They were originally developed to help test the tokenization logic of perltidy, but they have other uses. One use for --mangle is the following:
perltidy --mangle myfile.pl -st | perltidy -o myfile.pl.new
This will form the maximum possible number of one-line blocks (see next section), and can sometimes help clean up a badly formatted script.
A similar technique can be used with --extrude instead of --mangle to make the minimum number of one-line blocks.
Another use for --mangle is to combine it with -dac to reduce the file size of a perl script.
There are a few points to note regarding one-line blocks. A one-line block is something like this,
if ($x > 0) { $y = 1 / $x }
where the contents within the curly braces is short enough to fit on a single line.
With few exceptions, perltidy retains existing one-line blocks, if it is possible within the line-length constraint, but it does not attempt to form new ones. In other words, perltidy will try to follow the one-line block style of the input file.
If an existing one-line block is longer than the maximum line length, however, it will be broken into multiple lines. When this happens, perltidy checks for and adds any optional terminating semicolon (unless the -nasc option is used) if the block is a code block.
The main exception is that perltidy will attempt to form new one-line
blocks following the keywords map, eval, and sort, because
these code blocks are often small and most clearly displayed in a single
line.
One-line block rules can conflict with the cuddled-else option. When the cuddled-else option is used, perltidy retains existing one-line blocks, even if they do not obey cuddled-else formatting.
Occasionally, when one-line blocks get broken because they exceed the available line length, the formatting will violate the requested brace style. If this happens, reformatting the script a second time should correct the problem.
The following flags are available for debugging:
--dump-defaults or -ddf will write the default option set to standard output and quit
--dump-profile or -dpro will write the name of the current configuration file and its contents to standard output and quit.
--dump-options or -dop will write current option set to standard output and quit.
--dump-long-names or -dln will write all command line long names (passed to Get_options) to standard output and quit.
--dump-short-names or -dsn will write all command line short names to standard output and quit.
--dump-token-types or -dtt will write a list of all token types to standard output and quit.
--dump-want-left-space or -dwls will write the hash %want_left_space to standard output and quit. See the section on controlling whitespace around tokens.
--dump-want-right-space or -dwrs will write the hash %want_right_space to standard output and quit. See the section on controlling whitespace around tokens.
-DEBUG will write a file with extension .DEBUG for each input file showing the tokenization of all lines of code.
The first $VERSION line of a file which might be eval'd by MakeMaker is passed through unchanged except for indentation. Use --nopass-version-line, or -npvl, to deactivate this feature.
If the AutoLoader module is used, perltidy will continue formatting code after seeing an __END__ line. Use --nolook-for-autoloader, or -nlal, to deactivate this feature.
Likewise, if the SelfLoader module is used, perltidy will continue formatting code after seeing a __DATA__ line. Use --nolook-for-selfloader, or -nlsl, to deactivate this feature.
Perltidy contains a number of rules which help avoid known subtleties
and problems with older versions of perl, and these rules always
take priority over whatever formatting flags have been set. For example,
perltidy will usually avoid starting a new line with a bareword, because
this might cause problems if use strict is active.
There is no way to override these rules.
The flag -html causes perltidy to write an html file with extension .html. So, for example, the following command
perltidy -html somefile.pl
will produce a syntax-colored html file named somefile.pl.html which may be viewed with a browser.
Please Note: In this case, perltidy does not do any formatting to the input file, and it does not write a formatted file with extension .tdy. This means that two perltidy runs are required to create a fully reformatted, html copy of a script.
There are two options for formatting pod documentation. The default is to pass the pod through the Pod::Html module (which forms the basis of the pod2html utility). Any code sections are formatted by perltidy, and the results then merged. Note: perltidy creates a temporary file when Pod::Html is used; see "FILES". Also, Pod::Html creates temporary files for its cache.
NOTE: Perltidy counts the number of =cut lines, and either moves the
pod text to the top of the html file if there is one =cut, or leaves
the pod text in its original order (interleaved with code) otherwise.
Most of the flags accepted by pod2html may be included in the perltidy
command line, and they will be passed to pod2html. In some cases,
the flags have a prefix pod to emphasize that they are for the
pod2html, and this prefix will be removed before they are passed to
pod2html. The flags which have the additional pod prefix are:
--[no]podheader --[no]podindex --[no]podrecurse --[no]podquiet --[no]podverbose --podflush
The flags which are unchanged from their use in pod2html are:
--backlink=s --cachedir=s --htmlroot=s --libpods=s --title=s --podpath=s --podroot=s
where 's' is an appropriate character string. Not all of these flags are available in older versions of Pod::Html. See your Pod::Html documentation for more information.
The alternative, indicated with -npod, is not to use Pod::Html, but rather to format pod text in italics (or whatever the stylesheet indicates), without special html markup. This is useful, for example, if pod is being used as an alternative way to write comments.
By default, a single html output file is produced. This can be changed with the -frm option, which creates a frame holding a table of contents in the left panel and the source code in the right side. This simplifies code browsing. Assume, for example, that the input file is MyModule.pm. Then, for default file extension choices, these three files will be created:
MyModule.pm.html - the frame MyModule.pm.toc.html - the table of contents MyModule.pm.src.html - the formatted source code
Obviously this file naming scheme requires that output be directed to a real file (as opposed to, say, standard output). If this is not the case, or if the file extension is unknown, the -frm option will be ignored.
Style sheets make it very convenient to control and adjust the appearance of html pages. The default behavior is to write a page of html with an embedded style sheet.
An alternative to an embedded style sheet is to create a page with a link to an external style sheet. This is indicated with the -css=filename, where the external style sheet is filename. The external style sheet filename will be created if and only if it does not exist. This option is useful for controlling multiple pages from a single style sheet.
To cause perltidy to write a style sheet to standard output and exit, use the -ss, or --stylesheet, flag. This is useful if the style sheet could not be written for some reason, such as if the -pre flag was used. Thus, for example,
perltidy -html -ss >mystyle.css
will write a style sheet with the default properties to file mystyle.css.
The use of style sheets is encouraged, but a web page without a style sheets can be created with the flag -nss. Use this option if you must to be sure that older browsers (roughly speaking, versions prior to 4.0 of Netscape Navigator and Internet Explorer) can display the syntax-coloring of the html files.
Note: It is usually more convenient to accept the default properties and then edit the stylesheet which is produced. However, this section shows how to control the properties with flags to perltidy.
Syntax colors may be changed from their default values by flags of the either the long form, -html-color-xxxxxx=n, or more conveniently the short form, -hcx=n, where xxxxxx is one of the following words, and x is the corresponding abbreviation:
Token Type xxxxxx x
---------- -------- --
comment comment c
number numeric n
identifier identifier i
bareword, function bareword w
keyword keyword k
quite, pattern quote q
here doc text here-doc-text h
here doc target here-doc-target hh
punctuation punctuation pu
parentheses paren p
structural braces structure s
semicolon semicolon sc
colon colon co
comma comma cm
label label j
sub definition name subroutine m
pod text pod-text pd
A default set of colors has been defined, but they may be changed by providing values to any of the following parameters, where n is either a 6 digit hex RGB color value or an ascii name for a color, such as 'red'.
To illustrate, the following command will produce an html file somefile.pl.html with "aqua" keywords:
perltidy -html -hck=00ffff somefile.pl
and this should be equivalent for most browsers:
perltidy -html -hck=aqua somefile.pl
Perltidy merely writes any non-hex names that it sees in the html file. The following 16 color names are defined in the HTML 3.2 standard:
black => 000000, silver => c0c0c0, gray => 808080, white => ffffff, maroon => 800000, red => ff0000, purple => 800080, fuchsia => ff00ff, green => 008000, lime => 00ff00, olive => 808000, yellow => ffff00 navy => 000080, blue => 0000ff, teal => 008080, aqua => 00ffff,
Many more names are supported in specific browsers, but it is safest to use the hex codes for other colors. Helpful color tables can be located with an internet search for "HTML color tables".
Besides color, two other character attributes may be set: bold, and italics. To set a token type to use bold, use the flag --html-bold-xxxxxx or -hbx, where xxxxxx or x are the long or short names from the above table. Conversely, to set a token type to NOT use bold, use --nohtml-bold-xxxxxx or -nhbx.
Likewise, to set a token type to use an italic font, use the flag --html-italic-xxxxxx or -hix, where again xxxxxx or x are the long or short names from the above table. And to set a token type to NOT use italics, use --nohtml-italic-xxxxxx or -nhix.
For example, to use bold braces and lime color, non-bold, italics keywords the following command would be used:
perltidy -html -hbs -hck=00FF00 -nhbk -hik somefile.pl
The background color can be specified with --html-color-background=n, or -hcbg=n for short, where n is a 6 character hex RGB value. The default color of text is the value given to punctuation, which is black as a default.
Here are some notes and hints:
1. If you find a preferred set of these parameters, you may want to create a .perltidyrc file containing them. See the perltidy man page for an explanation.
2. Rather than specifying values for these parameters, it is probably easier to accept the defaults and then edit a style sheet. The style sheet contains comments which should make this easy.
3. The syntax-colored html files can be very large, so it may be best to split large files into smaller pieces to improve download times.
Several parameters which refer to code block types may be customized by also specifying an associated list of block types. The type of a block is the name of the keyword which introduces that block, such as if, else, or sub. An exception is a labeled block, which has no keyword, and should be specified with just a colon.
For example, the following parameter specifies sub, labels, BEGIN, and
END blocks:
-cscl="sub : BEGIN END"
(the meaning of the -cscl parameter is described above.) Note that quotes are required around the list of block types because of the spaces.
Several parameters allow default file extensions to be overridden. For
example, a backup file extension may be specified with -bext=ext,
where ext is some new extension. In order to provides the user some
flexibility, the following convention is used in all cases to decide if
a leading '.' should be used. If the extension ext begins with
A-Z, a-z, or 0-9, then it will be appended to the filename with
an intermediate '.' (or perhaps an '_' on VMS systems). Otherwise, it
will be appended directly.
For example, suppose the file is somefile.pl. For -bext=old, a '.' is
added to give somefile.pl.old. For -bext=.old, no additional '.' is
added, so again the backup file is somefile.pl.old. For -bext=~, then no
dot is added, and the backup file will be somefile.pl~ .
The following list shows all short parameter names which allow a prefix 'n' to produce the negated form:
D anl asc aws b bbb bbc bbs bl bli boc bok bol bot ce csc dac dbc dcsc ddf dln dnl dop dp dpro dsc dsm dsn dtt dwls dwrs dws f fll frm fs hsc html ibc icb icp iob isbc lal log lp lsl ohbr okw ola oll opr opt osbr otr ple ple pod pvl q sbc sbl schb scp scsb sct se sfp sfs skp sob sohb sop sosb sot ssc st sts syn t tac tbc toc tp tqw tsc w x bar kis
Equivalently, the prefix 'no' or 'no-' on the corresponding long names may be used.
Perltidy should work properly on most perl scripts. It does a lot of self-checking, but still, it is possible that an error could be introduced and go undetected. Therefore, it is essential to make careful backups and to test reformatted scripts.
The main current limitation is that perltidy does not scan modules included with 'use' statements. This makes it necessary to guess the context of any bare words introduced by such modules. Perltidy has good guessing algorithms, but they are not infallible. When it must guess, it leaves a message in the log file.
If you encounter a bug, please report it.
qw quotes.
Perltidy does not in any way modify the contents of here documents or
quoted text, even if they contain source code. (You could, however,
reformat them separately). Perltidy does not format 'format' sections
in any way. And, of course, it does not modify pod documents.
perlstyle(1), Perl::Tidy(3)
This man page documents perltidy version 20071205.
Michael Cartmell supplied code for adaptation to VMS and helped with v-strings.
Yves Orton supplied code for adaptation to the various versions of Windows.
Axel Rose supplied a patch for MacPerl.
Hugh S. Myers designed and implemented the initial Perl::Tidy module interface.
Many others have supplied key ideas, suggestions, and bug reports; see the CHANGES file.
Steve Hancock email: perltidy at users.sourceforge.net http://perltidy.sourceforge.net
Copyright (c) 2000-2006 by Steve Hancock
This package is free software; you can redistribute it and/or modify it under the terms of the "GNU General Public License".
Please refer to the file "COPYING" for details.
This package is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the "GNU General Public License" for more details.