PERLTIDY(1) User Contributed Perl Documentation PERLTIDY(1)NAMEperltidy - a perl script indenter and reformatter
SYNOPSISperltidy [ 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
DESCRIPTION
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 recom-
mendations 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 for-
matter which is described in "HTML OPTIONS".
EXAMPLESperltidy somefile.pl
This will produce a file somefile.pl.tdy containing the script refor-
matted 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 some-
file.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 "cud-
dled 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 some-
file.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), mymod-
ule.pm.toc.html (the table of contents), and mymodule.pm.src.html (the
source code).
OPTIONS - OVERVIEW
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 lead-
ing "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 --noout-
dent-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 iden-
tified. For example, instead of --dump-token-types, it would be suffi-
cient to enter --dump-tok, or even --dump-t, to uniquely identify this
command.
I/O control
The following parameters concern the files which are read and written.
-h, --help
Show summary of usage and exit.
-o=filename, --outfile=filename
Name of the output file (only if a single input file is being pro-
cessed). If no output file is specified, and output is not redi-
rected to the standard output, the output will go to filename.tdy.
-st, --standard-output
Perltidy must be able to operate on an arbitrarily large number of
files in a single run, with each output being directed to a differ-
ent 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 exam-
ple,
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.
-se, --standard-error-output
If perltidy detects an error when processing file somefile.pl, its
default behavior is to write error messages to file some-
file.pl.ERR. Use -se to cause all error messages to be sent to the
standard error output stream instead. This directive may be
negated with -nse. Thus, you may place -se in a .perltidyrc and
override it when desired with -nse on the command line.
-oext=ext, --output-file-extension=ext
Change the extension of the output file to be ext instead of the
default tdy (or html in case the --html option is used). See
"Specifying File Extensions".
-opath=path, --output-path=path
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 stan-
dard output, or if it is being specified explicitly with the -o=s
parameter.
-b, --backup-and-modify-in-place
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.
-bext=ext, --backup-file-extension=ext
Change the extension of the backup file to be something other than
the default .bak. See "Specifying File Extensions".
-w, --warning-output
Setting -w causes any non-critical warning messages to be reported
as errors. These include messages about possible pod problems,
possibly bad starting indentation level, and cautions about indi-
rect object usage. The default, -nw or --nowarning-output, is not
to include these warnings.
-q, --quiet
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.
-log, --logfile
Save the .LOG file, which has many useful diagnostics. Perltidy
always creates a .LOG file, but by default it is deleted unless a
program bug is suspected. Setting the -log flag forces the log
file to be saved.
-g=n, --logfile-gap=n
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 neces-
sary 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.
-npro--noprofile
Ignore any .perltidyrc command file. Normally, perltidy looks
first in your current directory for a .perltidyrc file of parame-
ters. (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.
-pro=filename or --profile=filename
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.
-opt, --show-options
Write a list of all options used to the .LOG file. Please see
--dump-options for a simpler way to do this.
-f, --force-read-binary
Force perltidy to process binary files. To avoid producing exces-
sive error messages, perltidy skips files identified by the system
as non-text. However, valid perl scripts containing binary data
may sometimes be identified as non-text, and this flag forces
perltidy to process them.
FORMATTING OPTIONS
Basic Options
-l=n, --maximum-line-length=n
The default maximum line length is n=80 characters. Perltidy will
try to find line break points to keep lines below this length. How-
ever, long quotes and side comments may cause lines to exceed this
length. Setting -l=0 is equivalent to setting -l=(a large number).
-i=n, --indent-columns=n
Use n columns per indentation level (default n=4).
tabs
Using tab characters will almost certainly lead to future portabil-
ity 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 out-
lined 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.
-et=n, --entab-leading-whitespace
This flag causes each n initial space characters to be replaced
by one tab character. Note that the integer n is completely
independent of the integer specified for indentation parameter,
-i=n.
-t, --tabs
This flag causes one leading tab character to be inserted for
each level of indentation. Certain other features are incom-
patible with this option, and if these options are also given,
then a warning message will be issued and this flag will be
unset. One example is the -lp option.
-syn, --check-syntax
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.
-pscf=s, -perl-syntax-check-flags=s
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.
-io, --indent-only
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.
-ole=s, --output-line-ending=s
where s="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.
-ple, --preserve-line-endings
This flag tells perltidy to write its output files with the same
line endings as the input file, if possible. It should work for
dos, unix, and mac line endings. It will only work if perltidy
input comes from a filename (rather than stdin, for example). If
perltidy has trouble determining the input file line ending, it
will revert to the default behavior of using the line ending of the
host system.
Code Indentation Control
-ci=n, --continuation-indentation=n
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.
-sil=n --starting-indentation-level=n
By default, perltidy examines the input file and tries to determine
the starting indentation level. While it is often zero, it may not
be zero for a code snippet being sent from an editing session. If
the default method does not work correctly, or you want to change
the starting level, use -sil=n, to force the starting level to be
n.
List indentation using -lp, --line-up-parentheses
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 open-
ing 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 abil-
ity 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.
-cti=n, --closing-token-indentation
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 inden-
tation 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 --clos-
ing-paren-indentation controls )'s, -csbi or --clos-
ing-square-bracket-indentation controls ]'s, -cbi or --clos-
ing-brace-indentation controls non-block }'s.
-icp, --indent-closing-paren
The -icp flag is equivalent to -cti=2, described in the previous
section. The -nicp flag is equivalent -cti=0. They are included
for backwards compatability.
-icb, --indent-closing-brace
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.
-olq, --outdent-long-quotes
When -olq is set, lines which is a quoted string longer than the
value maximum-line-length will have their indentation removed to
make them more readable. This is the default. To prevent such
out-denting, use -nolq or --nooutdent-long-lines.
-oll, --outdent-long-lines
This command is equivalent to --outdent-long-quotes and --out-
dent-long-comments, and it is included for compatibility with pre-
vious versions of perltidy. The negation of this also works, -noll
or --nooutdent-long-lines, and is equivalent to setting -nolq and
-nolc.
Outdenting Labels: -ola, --outdent-labels
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.
Outdenting Keywords
-okw, --outdent-keywords
The command -okw will will cause certain leading control key-
words 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.
Specifying Outdented Keywords: -okwl=string, --outdent-key-
word-list=string
This command can be used to change the keywords which are out-
dented 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 Control
Whitespace refers to the blank space between variables, operators, and
other code tokens.
-fws, --freeze-whitespace
This flag causes your original whitespace to remain unchanged, and
causes the rest of the whitespace commands in this section, the
Code Indentation section, and the Comment Control section to be
ignored.
Tightness of curly braces, parentheses, and square brackets.
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 con-
trols 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 con-
trolled 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
-sts, --space-terminal-semicolon
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
$i = 1; # -nsts (default)
-sfs, --space-for-semicolon
Semicolons within for loops may sometimes be hard to see, particu-
larly when commas are also present. This option places spaces on
both sides of these special semicolons, and is the default. Use
-nsfs or --nospace-for-semicolon to deactivate it.
for ( @a = @$ap, $u = shift @a ; @a ; $u = $v ) { # -sfs (default)
for ( @a = @$ap, $u = shift @a; @a; $u = $v ) { # -nsfs
-asc, --add-semicolons
Setting -asc allows perltidy to add any missing optional semicolon
at the end of a line which is followed by a closing curly brace on
the next line. This is the default, and may be deactivated with
-nasc or --noadd-semicolons.
-dsm, --delete-semicolons
Setting -dsm allows perltidy to delete extra semicolons which are
simply empty statements. This is the default, and may be deacti-
vated with -ndsm or --nodelete-semicolons. (Such semicolons are
not deleted, however, if they would promote a side comment to a
block comment).
-aws, --add-whitespace
Setting this option allows perltidy to add certain whitespace
improve code readability. This is the default. If you do not want
any whitespace added, but are willing to have some whitespace
deleted, use -naws. (Use -fws to leave whitespace completely
unchanged).
-dws, --delete-old-whitespace
Setting this option allows perltidy to remove some old whitespace
between characters, if necessary. This is the default. If you do
not want any old whitespace removed, use -ndws or
--nodelete-old-whitespace.
Detailed whitespace controls around tokens
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, contain-
ing 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 fol-
lowing two parameters would specify this desire:
-nwls="= + - / *" -nwrs="= + - / *"
(Note that the token types are in quotes, and that they are sepa-
rated by spaces). With these modified whitespace rules, the fol-
lowing 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 con-
flicts 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 cre-
ate 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.
Space between specific keywords and opening paren
When an opening paren follows a Perl keyword, no space is intro-
duced 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 exam-
ple,
my ( $a, $b, $c ) = @_; # default
my( $a, $b, $c ) = @_; # -nsak="my local our"
To put a space after all keywords, see the next item.
Space between all keywords and opening parens
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.
Space between all function names and opening parens
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, $c ); # -sfp
You will probably also want to use the flag -skp (previous item)
too.
Trimming whitespace around "qw" quotes
-tqw or --trim-qw provide the default behavior of trimming spaces
around multi-line "qw" quotes and indenting them appropriately.
-ntqw or --notrim-qw cause leading and trailing whitespace around
multi-line "qw" quotes to be left unchanged. This option will not
normally be necessary, but was added for testing purposes, because
in some versions of perl, trimming "qw" quotes changes the syntax
tree.
Comment Controls
Perltidy has a number of ways to control the appearance of both block
comments and side comments. The term block comment here refers to a
full-line comment, whereas side comment will refer to a comment which
appears on a line to the right of some code.
-ibc, --indent-block-comments
Block comments normally look best when they are indented to the
same level as the code which follows them. This is the default
behavior, but you may use -nibc to keep block comments left-justi-
fied. Here is an example:
# this comment is indented (-ibc, default)
if ($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.
-isbc, --indent-spaced-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.
-olc, --outdent-long-comments
When -olc is set, lines which are full-line (block) comments longer
than the value maximum-line-length will have their indentation
removed. This is the default; use -nolc to prevent outdenting.
-msc=n, --minimum-space-to-comment=n
Side comments look best when lined up several spaces to the right
of code. Perltidy will try to keep comments at least n spaces to
the right. The default is n=4 spaces.
-hsc, --hanging-side-comments
By default, perltidy tries to identify and align "hanging side com-
ments", 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.
Closing 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:
-csci=n, or --closing-side-comment-interval=n
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.
-cscp=string, or --closing-side-comment-prefix=string
where string is the prefix used before the name of the block
type. The default prefix, shown above, is "## 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 for-
mat them. Any comment identified as a closing side comment
will be placed just a single space to the right of its closing
brace.
-cscl=string, or --closing-side-comment-list-string
where "string" is a list of block types to be tagged with clos-
ing 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 exam-
ple, 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"
-csct=n, or --closing-side-comment-maximum-text=n
The text appended to certain block types, such as an "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 "...".
-csce=n, or --closing-side-comment-else-flag=n
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.
-cscw, or --closing-side-comment-warnings
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, differ-
ent 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 atten-
tion.
The intent is to avoid clobbering existing hand-written side
comments which happen to match the pattern of closing side com-
ments. This flag should only be needed on the first run with
-csc.
Important Notes on Closing Side Comments:
* Closing side comments are only placed on lines terminated with
a closing brace. Certain closing styles, such as the use of
cuddled elses (-ce), preclude the generation of some closing
side comments.
* Please note that adding or deleting of closing side comments
takes place only through the commands -csc or -dcsc. The other
commands, if used, merely modify the behavior of these two com-
mands.
* It is recommended that the -cscw flag be used along with -csc
on the first use of perltidy on a given file. This will pre-
vent loss of any existing side comment data which happens to
have the csc prefix.
* Once you use -csc, you should continue to use it so that any
closing side comments remain correct as code changes. Other-
wise, these comments will become incorrect as the code is
updated.
* If you edit the closing side comments generated by perltidy,
you must also change the prefix to be different from the clos-
ing side comment prefix. Otherwise, your edits will be lost
when you rerun perltidy with -csc. For example, you could
simply change "## 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.
* Temporarily generating closing side comments is a useful tech-
nique for exploring and/or debugging a perl script, especially
one written by someone else. You can always remove them with
-dcsc.
Static Block Comments
Static block comments are block comments with a special leading
pattern, "##" by default, which will be treated slightly differ-
ently 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.
-sbc, --static-block-comments
When -sbc is used, a block comment with a special leading pat-
tern, "##" by default, will be treated specially.
Comments so identified are treated as follows:
* If there is no leading space on the line, then the comment
will not be indented, and otherwise it may be,
* no new blank line will be inserted before such a comment,
and
* such a comment will never become a hanging side comment.
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.
-sbcp=string, --static-block-comment-prefix=string
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 white-
space. 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 iden-
tify 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.
-osbc, --outdent-static-block-comments
The command -osbc will will cause static block comments to be
outdented by 2 spaces (or whatever -ci=n has been set to), if
possible.
Static Side Comments
Static side comments are side comments with a special leading pat-
tern. This option can be useful for controlling how commented code
is displayed when it is a side comment.
-ssc, --static-side-comments
When -ssc is used, a side comment with a static leading pat-
tern, 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.
-sscp=string, --static-side-comment-prefix=string
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 iden-
tify 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.
Skipping Selected Sections of Code
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 work-
ing around occasional problems. For example it might be useful for
keeping the indentation of old commented code unchanged, keeping inden-
tation of long blocks of aligned comments unchanged, keeping certain
list formatting unchanged, or working around a glitch in perltidy.
-fs, --format-skipping
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 com-
ment 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.
-fsb=string, --format-skipping-begin=string
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 back-
slashes for characters to be taken literally rather than as pat-
terns.
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 #*****
-fse=string, --format-skipping-end=string
The -fsb=string is the corresponding parameter used to change the
ending marker for format skipping. The default is equivalent to
-fse='#<<<'.
Line Break Control
-fnl, --freeze-newlines
If you do not want any changes to the line breaks in your script,
set -fnl, and they will remain fixed, and the rest of the commands
in this section and sections "Controlling List Formatting",
"Retaining or Ignoring Existing Line Breaks", and "Blank Line Con-
trol" will be ignored. You may want to use -noll with this.
-ce, --cuddled-else
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();
}
-bl, --opening-brace-on-new-line
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 ( $input_file eq '-' ) { # -nbl (default)
-sbl, --opening-sub-brace-on-new-line
The flag -sbl can be used to override the value of -bl for opening
sub braces. For example,
perltidy-sbl
produces this result:
sub message
{
if (!defined($_[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.
-bli, --brace-left-and-indent
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.
-blil=s, --brace-left-and-indent-list=s
Use this parameter to change the types of block braces for which
the -bli flag applies; see "Specifying Block Types". For example,
-blil='if elsif else' would apply it to only "if/elsif/else"
blocks.
-bar, --opening-brace-always-on-right
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 key-
word, 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.
-otr, --opening-token-right and related flags
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 sepa-
rately if desired:
-opr or --opening-paren-right
-ohbr or --opening-hash-brace-right
-osbr or --opening-square-bracket-right
Vertical tightness of non-block curly braces, parentheses, and square
brackets.
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
* You must also use the -lp flag when you use the -vt flag; the
reason is explained below.
* 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 bal-
ance between tightness and readability in complex lists.
* Different controls may be applied to to different token types,
and it is also possible to control block braces; see below.
* Finally, please note that these vertical tightness flags are
merely hints to the formatter, and it cannot always follow
them. Things which make it difficult or impossible include
comments, blank lines, blocks of code within a list, and possi-
bly the lack of the -lp parameter. Also, these flags may be
ignored for very small lists (2 or 3 lines in length).
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 parame-
ter.
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-verti-
cal-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-ver-
tical-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.
-bbvt=n or --block-brace-vertical-tightness=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 imple-
mented 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.
-sot, --stack-opening-token and related flags
The -sot flag tells perltidy to "stack" opening tokens when possi-
ble 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.
-sct, --stack-closing-token and related flags
The -sct flag tells perltidy to "stack" closing tokens when possi-
ble 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 "hid-
ing" 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 exam-
ple:
# -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.
-dnl, --delete-old-newlines
By default, perltidy first deletes all old line break locations,
and then it looks for good break points to match the desired line
length. Use -ndnl or --nodelete-old-newlines to force perltidy to
retain all old line break points.
-anl, --add-newlines
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.
Controlling whether perltidy breaks before or after operators
Two command line parameters provide some control over whether a
line break should be before or after specific token types.
-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, contain-
ing 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 con-
flicts with hardwired logic which cause unexpected results. One
example is curly braces, which should be controlled with the param-
eter bl provided for that purpose.
WARNING Be sure to put these tokens in quotes to avoid having them
misinterpreted by your command shell.
Controlling List Formatting
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.
-boc, --break-at-old-comma-breakpoints
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".
-mft=n, --maximum-fields-per-table=n
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 gen-
eral 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 format-
ting in future applications of perltidy.
# perltidy -mft=2
@month_of_year = (
'Jan', 'Feb',
'Mar', 'Apr',
'May', 'Jun',
'Jul', 'Aug',
'Sep', 'Oct',
'Nov', 'Dec'
);
-cab=n, --comma-arrow-breakpoints=n
A comma which follows a comma arrow, '=>', requires special consid-
eration. 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
);
Retaining or Ignoring Existing Line Breaks
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.
-bol, --break-at-old-logical-breakpoints
By default, if a logical expression is broken at a "&&", "||",
"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.
-bok, --break-at-old-keyword-breakpoints
By default, perltidy will retain a breakpoint before keywords which
may return lists, such as "sort" and <map>. This allows chains of
these operators to be displayed one per line. Use -nbok to prevent
retaining these breakpoints.
-bot, --break-at-old-ternary-breakpoints
By default, if a conditional (ternary) operator is broken at a ":",
then it will remain broken. To prevent this, and thereby form
longer lines, use -nbot.
-iob, --ignore-old-breakpoints
Use this flag to tell perltidy to ignore existing line breaks to
the maximum extent possible. This will tend to produce the longest
possible containers, regardless of type, which do not exceed the
line length limit.
Blank Line Control
Blank lines can improve the readability of a script if they are care-
fully placed. Perltidy has several commands for controlling the inser-
tion, retention, and removal of blank lines.
-bbc, --blanks-before-comments
A blank line will be introduced before a full-line comment. This
is the default. Use -nbbc or --noblanks-before-comments to pre-
vent such blank lines from being introduced.
-bbs, --blanks-before-subs
A blank line will be introduced before a sub definition, unless it
is a one-liner or preceded by a comment. A blank line will also be
introduced before a package statement and a BEGIN and END block.
This is the default. The intention is to help display the struc-
ture of a program by setting off certain key sections of code.
This is negated with -nbbs or --noblanks-before-subs.
-bbb, --blanks-before-blocks
A blank line will be introduced before blocks of coding delimited
by for, foreach, while, until, and if, unless, in the following
circumstances:
* The block is not preceded by a comment.
* The block is not a one-line block.
* The number of consecutive non-blank lines at the current inden-
tation depth is at least -lbl (see next section).
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.
-lbl=n --long-block-line-count=n
This controls how often perltidy is allowed to add blank lines
before certain block types (see previous section). The default is
8. Entering a value of 0 is equivalent to entering a very large
number.
-mbl=n --maximum-consecutive-blank-lines=n
This parameter specifies the maximum number of consecutive blank
lines in the output script. The default is n=1. If the input file
has more than n consecutive blank lines, the number will be reduced
to n. (This obviously does not apply to pod sections, here-docu-
ments, and quotes).
-sob, --swallow-optional-blank-lines
All blank lines not required by the above flags, -bbb, -bbs, and
-bbc, will be deleted. (But essential blank lines above pod docu-
ments will be retained). This is NOT the default.
-nsob, --noswallow-optional-blank-lines
Retain blank lines, including those which do not corresponding to
flags -bbb, -bbs, and -bbc. This is the default. The number of
blanks retained is subject to the limit imposed by --maximum-con-
secutive-blank-lines, however.
Styles
A style refers to a convenient collection of existing parameters.
-gnu, --gnu-style
-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 parame-
ters:
-lp -bl -noll -pt=2 -bt=2 -sbt=2 -icp
-pbp, --perl-best-practices
-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 nec-
essary.
Other Controls
Deleting selected text
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).
Writing selected text to a file
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.
Using a .perltidyrc command file
If you use perltidy frequently, you probably won't be happy until
you create a .perltidyrc file to avoid typing commonly-used parame-
ters. 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
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
* It may be simplest to develop and test configuration files with
alternative names, and invoke them with -pro=filename on the
command line. Then rename the desired file to .perltidyrc when
finished.
* The parameters in the .perltidyrc file can be switched off with
the -npro option.
* The commands --dump-options, --dump-defaults,
--dump-long-names, and --dump-short-names, all described below,
may all be helpful.
Creating a new abbreviation
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).
Skipping leading non-perl commands with -x or --look-for-hash-bang
If your script has leading lines of system commands or other text
which are not valid perl code, and which are separated from the
start of the perl code by a "hash-bang" line, ( a line of the form
"#!...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 inter-
active VMS scripts, but it should be used for any script which is
normally invoked with "perl -x".
Making a file unreadable
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 tok-
enization 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.
One-line blocks
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 dis-
played 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.
Debugging
The following flags are available for debugging:
--dump-defaults or -ddf will write the default option set to stan-
dard output and quit
--dump-profile or -dpro will write the name of the current config-
uration 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.
Working with MakeMaker, AutoLoader and SelfLoader
The first $VERSION line of a file which might be eval'd by Make-
Maker 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.
Working around problems with older version of Perl
Perltidy contains a number of rules which help avoid known sub-
tleties 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.
HTML OPTIONS
The -html master switch
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 exten-
sion .tdy. This means that two perltidy runs are required to cre-
ate a fully reformatted, html copy of a script.
The -pre flag for code snippets
When the -pre flag is given, only the pre-formatted section, within
the <PRE> and </PRE> tags, will be output. This simplifies inclu-
sion of the output in other files. The default is to output a com-
plete web page.
The -nnn flag for line numbering
When the -nnn flag is given, the output lines will be numbered.
The -toc, or --html-table-of-contents flag
By default, a table of contents to packages and subroutines will be
written at the start of html output. Use -ntoc to prevent this.
This might be useful, for example, for a pod document which con-
tains a number of unrelated code snippets. This flag only influ-
ences the code table of contents; it has no effect on any table of
contents produced by pod2html (see next item).
The -pod, or --pod2html flag
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 exam-
ple, if pod is being used as an alternative way to write comments.
The -frm, or --frames flag
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.
The -text=s, or --html-toc-extension flag
Use this flag to specify the extra file extension of the table of
contents file when html frames are used. The default is "toc".
See "Specifying File Extensions".
The -sext=s, or --html-src-extension flag
Use this flag to specify the extra file extension of the content
file when html frames are used. The default is "src". See "Speci-
fying File Extensions".
The -hent, or --html-entities flag
This flag controls the use of Html::Entities for html formatting.
By default, the module Html::Entities is used to encode special
symbols. This may not be the right thing for some browser/language
combinations. Use --nohtml-entities or -nhent to prevent this.
Style Sheets
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 dis-
play the syntax-coloring of the html files.
Controlling HTML properties
Note: It is usually more convenient to accept the default proper-
ties 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 conve-
niently the short form, -hcx=n, where xxxxxx is one of the follow-
ing 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-back-
ground=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 punctua-
tion, 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 proba-
bly 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.
SOME COMMON INPUT CONVENTIONS
Specifying Block Types
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 spa-
ces.
Specifying File Extensions
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 flexi-
bility, 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~ .
SWITCHES WHICH MAY BE NEGATED
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
Equivalently, the prefix 'no' or 'no-' on the corresponding long names
may be used.
LIMITATIONS
Parsing Limitations
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.
What perltidy does not parse and format
Perltidy indents but does not reformat comments and "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, how-
ever, reformat them separately). Perltidy does not format 'format'
sections in any way. And, of course, it does not modify pod docu-
ments.
FILES
Temporary files
Under the -html option with the default --pod2html flag, a tempo-
rary file is required to pass text to Pod::Html. Unix systems will
try to use the POSIX tmpnam() function. Otherwise the file
perltidy.TMP will be temporarily created in the current working
directory.
Special files when standard input is used
When standard input is used, the log file, if saved, is
perltidy.LOG, and any errors are written to perltidy.ERR unless the
-se flag is set. These are saved in the current working directory.
Files overwritten
The following file extensions are used by perltidy, and files with
these extensions may be overwritten or deleted: .ERR, .LOG, .TEE,
and/or .tdy, .html, and .bak, depending on the run type and set-
tings.
Files extensions limitations
Perltidy does not operate on files for which the run could produce
a file with a duplicated file extension. These extensions include
.LOG, .ERR, .TEE, and perhaps .tdy and .bak, depending on the run
type. The purpose of this rule is to prevent generating confusing
filenames such as somefile.tdy.tdy.tdy.
SEE ALSOperlstyle(1), Perl::Tidy(3)VERSION
This man page documents perltidy version 20070508.
CREDITS
Michael Cartmell supplied code for adaptation to VMS and helped with
v-strings.
Yves Orton supplied code for adaptation to the various versions of Win-
dows.
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.
AUTHOR
Steve Hancock
email: perltidy at users.sourceforge.net
http://perltidy.sourceforge.net
COPYRIGHT
Copyright (c) 2000-2006 by Steve Hancock
LICENSE
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.
DISCLAIMER
This package is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of MER-
CHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the "GNU General Public License" for more details.
perl v5.8.8 2007-05-08 PERLTIDY(1)
