perlcritic(1) User Contributed Perl Documentation perlcritic(1)
NAME
"perlcritic" - Command-line interface to critique Perl source.
SYNOPSIS
perlcritic [-12345 | --brutal | --cruel | --harsh | --stern | --gentle]
[--severity number | name] [{-p | --profile} file | --noprofile]
[--top [ number ]] [--theme expression] [--include pattern]
[--exclude pattern] [{-s | --single-policy} pattern]
[--only | --noonly] [--profile-strictness {warn|fatal|quiet}]
[--force | --noforce] [--statistics] [--statistics-only]
[--count | -C] [--verbose {number | format}] [--allow-unsafe]
[--color | --nocolor] [--pager pager] [--quiet]
[--color-severity-highest color_specification]
[--color-severity-high color_specification]
[--color-severity-medium color_specification]
[--color-severity-low color_specification]
[--color-severity-lowest color_specification]
[--files-with-violations | -l]
[--files-without-violations | -L]
[--program-extensions file_name_extension]
{FILE | DIRECTORY | STDIN}
perlcritic --profile-proto
perlcritic { --list | --list-enabled | --list-themes | --doc pattern [...] }
perlcritic { --help | --options | --man | --version }
DESCRIPTION
"perlcritic" is a Perl source code analyzer. It is the executable
front-end to the Perl::Critic engine, which attempts to identify
awkward, hard to read, error-prone, or unconventional constructs in
your code. Most of the rules are based on Damian Conway's book Perl
Best Practices. However, "perlcritic" is not limited to enforcing PBP,
and it will even support rules that contradict Conway. All rules can
easily be configured or disabled to your liking.
This documentation only covers how to drive this command. For all
other information, such as API reference and alternative interfaces,
please see the documentation for Perl::Critic itself.
USAGE EXAMPLES
Before getting into all the gory details, here are some basic usage
examples to help get you started.
# Report only most severe violations (severity = 5)
perlcritic YourModule.pm
# Same as above, but read input from STDIN
perlcritic
# Recursively process all Perl files beneath directory
perlcritic /some/directory
# Report slightly less severe violations too (severity >= 4)
perlcritic -4 YourModule.pm
# Same as above, but using named severity level
perlcritic --stern YourModule.pm
# Report all violations, regardless of severity (severity >= 1)
perlcritic -1 YourModule.pm
# Same as above, but using named severity level
perlcritic --brutal YourModule.pm
# Report only violations of things from "Perl Best Practices"
perlcritic --theme pbp YourModule.pm
# Report top 20 most severe violations (severity >= 1)
perlcritic --top YourModule.pm
# Report additional violations of Policies that match m/variables/xms
perlcritic --include variables YourModule.pm
# Use defaults from somewhere other than ~/.perlcriticrc
perlcritic --profile project/specific/perlcriticrc YourModule.pm
ARGUMENTS
The arguments are paths to the files you wish to analyze. You may
specify multiple files. If an argument is a directory, "perlcritic"
will analyze all Perl files below the directory. If no arguments are
specified, then input is read from STDIN.
OPTIONS
Option names can be abbreviated to uniqueness and can be stated with
singe or double dashes, and option values can be separated from the
option name by a space or '=' (as with Getopt::Long). Option names are
also case-sensitive.
"--profile FILE" or "-p FILE"
Directs "perlcritic" to use a profile named by FILE rather than
looking for the default .perlcriticrc file in the current directory
or your home directory. See "CONFIGURATION" in Perl::Critic for
more information.
"--noprofile"
Directs "perlcritic" not to load any configuration file, thus
reverting to the default configuration for all Policies.
"--severity N"
Directs "perlcritic" to only apply Policies with a severity greater
than "N". Severity values are integers ranging from 1 (least
severe) to 5 (most severe). The default is 5. For a given
"--profile", decreasing the "--severity" will usually produce more
violations. You can set the default value for this option in your
.perlcriticrc file. You can also redefine the "severity" for any
Policy in your .perlcriticrc file. See "CONFIGURATION" for more
information.
"-5 | -4 | -3 | -2 | -1"
These are numeric shortcuts for setting the "--severity" option.
For example, "-4" is equivalent to "--severity 4". If multiple
shortcuts are specified, then the most restrictive one wins. If an
explicit "--severity" option is also given, then all shortcut
options are silently ignored. NOTE: Be careful not to put one of
the number severity shortcut options immediately after the "--top"
flag or "perlcritic" will interpret it as the number of violations
to report.
"--severity NAME"
If it is difficult for you to remember whether severity "5" is the
most or least restrictive level, then you can use one of these
named values:
SEVERITY NAME ...is equivalent to... SEVERITY NUMBER
--------------------------------------------------------
--severity gentle --severity 5
--severity stern --severity 4
--severity harsh --severity 3
--severity cruel --severity 2
--severity brutal --severity 1
"--gentle | --stern | --harsh | --cruel | --brutal"
These are named shortcuts for setting the "--severity" option. For
example, "--cruel" is equivalent to "--severity 2". If multiple
shortcuts are specified, then the most restrictive one wins. If an
explicit "--severity" option is also given, then all shortcut
options are silently ignored.
"--theme RULE"
Directs "perlcritic" to apply only Policies with themes that
satisfy the "RULE". Themes are arbitrary names for groups of
related policies. You can combine theme names with boolean
operators to create an arbitrarily complex "RULE". For example,
the following would apply only Policies that have a 'bugs' AND
'pbp' theme:
$> perlcritic --theme='bugs && pbp' MyModule.pm
Unless the "--severity" option is explicitly given, setting
"--theme" silently causes the "--severity" to be set to 1. You can
set the default value for this option in your .perlcriticrc file.
See "POLICY THEMES" in Perl::Critic for more information about
themes.
"--include PATTERN"
Directs "perlcritic" to apply additional Policies that match the
regex "/PATTERN/imx". Use this option to temporarily override your
profile and/or the severity settings at the command-line. For
example:
perlcritic --include=layout my_file.pl
This would cause "perlcritic" to apply all the "CodeLayout::*"
policies even if they have a severity level that is less than the
default level of 5, or have been disabled in your .perlcriticrc
file. You can specify multiple "--include" options and you can use
it in conjunction with the "--exclude" option. Note that
"--exclude" takes precedence over "--include" when a Policy matches
both patterns. You can set the default value for this option in
your .perlcriticrc file.
"--exclude PATTERN"
Directs "perlcritic" to not apply any Policy that matches the regex
"/PATTERN/imx". Use this option to temporarily override your
profile and/or the severity settings at the command-line. For
example:
perlcritic --exclude=strict my_file.pl
This would cause "perlcritic" to not apply the "RequireUseStrict"
and "ProhibitNoStrict" Policies even though they have the highest
severity level. You can specify multiple "--exclude" options and
you can use it in conjunction with the "--include" option. Note
that "--exclude" takes precedence over "--include" when a Policy
matches both patterns. You can set the default value for this
option in your .perlcriticrc file.
"--single-policy PATTERN" or "-s PATTERN"
Directs "perlcritic" to apply just one Policy module matching the
regex "/PATTERN/ixms", and exclude all other Policies. This option
has precedence over the "--severity", "--theme", "--include",
"--exclude", and "--only" options. For example:
perlcritic --single-policy=nowarnings my_file.pl
This would cause "perlcritic" to apply just the
"ProhibitNoWarnings" Policy, regardless of the severity level
setting. No other Policies would be applied.
This is equivalent to what one might intend by...
perlcritic --exclude=. --include=nowarnings my_file.pl
... but this won't work because the "--exclude" option overrides
the "--include" option.
The equivalent of this option can be accomplished by creating a
custom profile containing only the desired policy and then
running...
perlcritic --profile=customprofile --only my_file.pl
"--top [ N ]"
Directs "perlcritic" to report only the top "N" Policy violations
in each file, ranked by their severity. If "N" is not specified,
it defaults to 20. If the "--severity" option (or one of the
shortcuts) is not explicitly given, the "--top" option implies that
the minimum severity level is "1" (i.e. "brutal"). Users can
redefine the severity for any Policy in their .perlcriticrc file.
See "CONFIGURATION" for more information. You can set the default
value for this option in your .perlcriticrc file. NOTE: Be careful
not to put one of the severity shortcut options immediately after
the "--top" flag or "perlcritic" will interpret it as the number of
violations to report.
"--force"
Directs "perlcritic" to ignore the magical "## no critic"
annotations in the source code. See "BENDING THE RULES" for more
information. You can set the default value for this option in your
.perlcriticrc file.
"--statistics"
Causes several statistics about the code being scanned and the
violations found to be reported after any other output.
"--statistics-only"
Like the "--statistics" option, but suppresses normal output and
only shows the statistics.
"--verbose N | FORMAT"
Sets the verbosity level or format for reporting violations. If
given a number ("N"), "perlcritic" reports violations using one of
the predefined formats described below. If given a string
("FORMAT"), it is interpreted to be an actual format specification.
If the "--verbose" option is not specified, it defaults to either 4
or 5, depending on whether multiple files were given as arguments
to "perlcritic". You can set the default value for this option in
your .perlcriticrc file.
Verbosity Format Specification
----------- -------------------------------------------------------
1 "%f:%l:%c:%m\n",
2 "%f: (%l:%c) %m\n",
3 "%m at %f line %l\n",
4 "%m at line %l, column %c. %e. (Severity: %s)\n",
5 "%f: %m at line %l, column %c. %e. (Severity: %s)\n",
6 "%m at line %l, near '%r'. (Severity: %s)\n",
7 "%f: %m at line %l near '%r'. (Severity: %s)\n",
8 "[%p] %m at line %l, column %c. (Severity: %s)\n",
9 "[%p] %m at line %l, near '%r'. (Severity: %s)\n",
10 "%m at line %l, column %c.\n %p (Severity: %s)\n%d\n",
11 "%m at line %l, near '%r'.\n %p (Severity: %s)\n%d\n"
Formats are a combination of literal and escape characters similar
to the way "sprintf" works. See String::Format for a full
explanation of the formatting capabilities. Valid escape
characters are:
Escape Meaning
------- ------------------------------------------------------------
%c Column number where the violation occurred
%d Full diagnostic discussion of the violation
%e Explanation of violation or page numbers in PBP
%F Just the name of the file where the violation occurred.
%f Path to the file where the violation occurred.
%l Line number where the violation occurred
%m Brief description of the violation
%P Full name of the Policy module that created the violation
%p Name of the Policy without the Perl::Critic::Policy:: prefix
%r The string of source code that caused the violation
%C The class of the PPI::Element that caused the violation
%s The severity level of the violation
The purpose of these formats is to provide some compatibility with
text editors that have an interface for parsing certain kinds of
input. See "EDITOR INTEGRATION" for more information about that.
"--list"
Displays a condensed listing of all the Perl::Critic::Policy
modules that are found on this machine. This option lists all
Policies, regardless of your .perlcriticrc or command line options.
For each Policy, the name, default severity and default themes are
shown.
"--list-enabled"
Displays a condensed listing of all the Perl::Critic::Policy
modules that would be enforced, if you were actually going to
critique a file with this command. This is useful when you've
constructed a complicated command or modified your .perlcriticrc
file and you want to see exactly which Policies are going to be
enforced (or not enforced, as the case may be). For each Policy,
the name, default severity and default themes are shown.
"--list-themes"
Displays a list of all the themes of the Perl::Critic::Policy
modules that are found on this machine.
"--profile-proto"
Displays an expanded listing of all the Perl::Critic::Policy
modules that are found on this machine. For each Policy, the name,
default severity and default themes are shown, as well as the name
of any additional parameters that the Policy supports. The format
is suitable as a prototype for your .perlcriticrc file.
"--only"
Directs perlcritic to apply only Policies that are explicitly
mentioned in your .perlcriticrc file. This is useful if you want
to use just a small subset of Policies without having to disable
all the others. You can set the default value for this option in
your .perlcriticrc file.
"--profile-strictness {warn|fatal|quiet}"
Directs perlcritic how to treat certain recoverable problems found
in a .perlcriticrc or file specified via the "--profile" option.
Valid values are "warn" (the default), "fatal", and "quiet". For
example, perlcritic normally only warns about profiles referring to
non-existent Policies, but this option can make this situation
fatal. You can set the default value for this option in your
.perlcriticrc file.
"--count"
"-C"
Display only the number of violations for each file. Use this
feature to get a quick handle on where a large pile of code might
need the most attention.
"--color"
"--colour"
This option is on when outputting to a tty. When set, Severity 5
and 4 are colored red and yellow, respectively. Colorization only
happens if Term::ANSIColor is installed. For Windows environments,
Win32::Console::ANSI must also be installed. Negate this switch to
disable color. You can set the default value for this option in
your .perlcriticrc file.
"--pager PAGER_COMMAND_STRING"
If set, perlcritic will pipe it's output to the given
PAGER_COMMAND_STRING. You can set the default value for this
option in your .perlcriticrc file.
Setting a pager turns off color by default. You will have to turn
color on explicitly. If you want color, you'll probably also want
to tell your pager to display raw characters. For "less" and
"more", use the -R switch.
"--color-severity-highest COLOR_SPECIFICATION"
Specifies the color to be used for highest severity violations, as
a Term::ANSIColor color specification. Can also be specified as
"--colour- severity-highest", "--color-severity-5", or
"--colour-severity-5".
"--color-severity-high COLOR_SPECIFICATION"
Specifies the color to be used for high severity violations, as a
Term::ANSIColor color specification. Can also be specified as
"--colour- severity-high", "--color-severity-4", or
"--colour-severity-4".
"--color-severity-medium COLOR_SPECIFICATION"
Specifies the color to be used for medium severity violations, as a
Term::ANSIColor color specification. Can also be specified as
"--colour- severity-medium", "--color-severity-3", or
"--colour-severity-3".
"--color-severity-low COLOR_SPECIFICATION"
Specifies the color to be used for low severity violations, as a
Term::ANSIColor color specification. Can also be specified as
"--colour- severity-low", "--color-severity-2", or
"--colour-severity-2".
"--color-severity-lowest COLOR_SPECIFICATION"
Specifies the color to be used for lowest severity violations, as a
Term::ANSIColor color specification. Can also be specified as
"--colour- severity-lowest", "--color-severity-1", or
"--colour-severity-1".
"--files-with-violations"
Display only the names of files with violations. Use this feature
with --single-policy to find files that contain violations of a
given policy. Can also be specified as "--l".
"--files-without-violations"
Display only the names of files without violations. Use this
feature with --single-policy to find files that do not contain
violations of a given policy. Can also be specified as "--L".
"--program-extensions file_name_extension"
Tell "perlcritic" to treat files whose names end in the given file
name extension as programs, not as modules. If a leading '.' is
desired it must be explicitly specified, e.g.
--program-extensions .pl
The matching is case-sensitive, and the option may be specified as
many times as desired, e.g.
--program-extensions .pl --program-extensions .cgi
The above can also be done by quoting the file name extensions:
--program-extensions '.pl .cgi'
Files whose name ends in '.PL' will always be considered programs.
"--doc PATTERN"
Displays the perldoc for all Perl::Critic::Policy modules that
match "m/PATTERN/ixms". Since Policy modules tend to have rather
long names, this just provides a more convenient way to say
something like: "perldoc
Perl::Critic::Policy::ValuesAndExpressions::RequireUpperCaseH
eredocTerminator" at the command prompt.
"--allow-unsafe"
This option directs "perlcritic" to allow the use of Policies that
have been marked as "unsafe". Unsafe Policies may result in risky
operations by compiling and executing the code they analyze. All
the Policies that ship in the core Perl::Critic distribution are
safe. However, third- party Policies, such as those in the
Perl::Critic::Dynamic distribution are not safe. Note that "safety"
is honorary -- if a Policy author marks a Policy as safe, it is not
a guarantee that it won't do nasty things. If you don't trust your
Policies and the code you are analyzing, then do not use this
switch.
"--quiet"
Suppress the "source OK" message when no violations are found.
"--help"
"-?"
"-H"
Displays a brief summary of options and exits.
"--options"
Displays the descriptions of the options and exits. While this
output is long, it it nowhere near the length of the output of
"--man".
"--man"
Displays the complete "perlcritic" manual and exits.
"--version"
"-V"
Displays the version number of "perlcritic" and exits.
CONFIGURATION
Most of the settings for Perl::Critic and each of the Policy modules
can be controlled by a configuration file. The default configuration
file is called .perlcriticrc. "perlcritic" will look for this file in
the current directory first, and then in your home directory.
Alternatively, you can set the "PERLCRITIC" environment variable to
explicitly point to a different file in another location. If none of
these files exist, and the "--profile" option is not given on the
command-line, then all Policies will be loaded with their default
configuration.
The format of the configuration file is a series of INI-style blocks
that contain key-value pairs separated by "=". Comments should start
with "#" and can be placed on a separate line or after the name-value
pairs if you desire.
Default settings for perlcritic itself can be set before the first
named block. For example, putting any or all of these at the top of
your .perlcriticrc file will set the default value for the
corresponding command-line argument.
severity = 3 #Integer or named level
only = 1 #Zero or One
force = 0 #Zero or One
verbose = 4 #Integer or format spec
top = 50 #A positive integer
theme = (pbp + security) * bugs #A theme expression
include = NamingConventions ClassHierarchies #Space-delimited list
exclude = Variables Modules::RequirePackage #Space-delimited list
The remainder of the configuration file is a series of blocks like
this:
[Perl::Critic::Policy::Category::PolicyName]
severity = 1
set_themes = foo bar
add_themes = baz
arg1 = value1
arg2 = value2
"Perl::Critic::Policy::Category::PolicyName" is the full name of a
module that implements the policy. The Policy modules distributed with
Perl::Critic have been grouped into categories according to the table
of contents in Damian Conway's book Perl Best Practices. For brevity,
you can omit the 'Perl::Critic::Policy' part of the module name.
"severity" is the level of importance you wish to assign to the Policy.
All Policy modules are defined with a default severity value ranging
from 1 (least severe) to 5 (most severe). However, you may disagree
with the default severity and choose to give it a higher or lower
severity, based on your own coding philosophy. You can set the
"severity" to an integer from 1 to 5, or use one of the equivalent
names:
SEVERITY NAME ...is equivalent to... SEVERITY NUMBER
----------------------------------------------------
gentle 5
stern 4
harsh 3
cruel 2
brutal 1
"set_themes" sets the theme for the Policy and overrides its default
theme. The argument is a string of one or more whitespace-delimited
alphanumeric words. Themes are case-insensitive. See "POLICY THEMES"
for more information.
"add_themes" appends to the default themes for this Policy. The
argument is a string of one or more whitespace-delimited words. Themes
are case- insensitive. See "POLICY THEMES" for more information.
The remaining key-value pairs are configuration parameters that will be
passed into the constructor of that Policy. The constructors for most
Policy modules do not support arguments, and those that do should have
reasonable defaults. See the documentation on the appropriate Policy
module for more details.
Instead of redefining the severity for a given Policy, you can
completely disable a Policy by prepending a '-' to the name of the
module in your configuration file. In this manner, the Policy will
never be loaded, regardless of the "--severity" given on the command
line.
A simple configuration might look like this:
#--------------------------------------------------------------
# I think these are really important, so always load them
[TestingAndDebugging::RequireUseStrict]
severity = 5
[TestingAndDebugging::RequireUseWarnings]
severity = 5
#--------------------------------------------------------------
# I think these are less important, so only load when asked
[Variables::ProhibitPackageVars]
severity = 2
[ControlStructures::ProhibitPostfixControls]
allow = if unless # My custom configuration
severity = cruel # Same as "severity = 2"
#--------------------------------------------------------------
# Give these policies a custom theme. I can activate just
# these policies by saying "perlcritic --theme 'larry || curly'"
[Modules::RequireFilenameMatchesPackage]
add_themes = larry
[TestingAndDebugging::RequireTestLabels]
add_themes = curly moe
#--------------------------------------------------------------
# I do not agree with these at all, so never load them
[-NamingConventions::Capitalization]
[-ValuesAndExpressions::ProhibitMagicNumbers]
#--------------------------------------------------------------
# For all other Policies, I accept the default severity,
# so no additional configuration is required for them.
Note that all policies included with the Perl::Critic distribution that
have integer parameters accept underscores ("_") in their values, as
with Perl numeric literals. For example,
[ValuesAndExpressions::RequireNumberSeparators]
min_value = 1_000
For additional configuration examples, see the perlcriticrc file that
is included in this examples directory of this distribution.
Damian Conway's own Perl::Critic configuration is also included in this
distribution as examples/perlcriticrc-conway.
THE POLICIES
A large number of Policy modules are distributed with Perl::Critic.
They are described briefly in the companion document
Perl::Critic::PolicySummary and in more detail in the individual
modules themselves. Say "perlcritic --doc PATTERN" to see the perldoc
for all Policy modules that match the regex "m/PATTERN/ixms"
There are a number of distributions of additional policies on CPAN. If
Perl::Critic doesn't contain a policy that you want, some one may have
already written it. See "SEE ALSO" in Perl::Critic for a list of some
of these distributions.
POLICY THEMES
Each Policy is defined with one or more "themes". Themes can be used
to create arbitrary groups of Policies. They are intended to provide
an alternative mechanism for selecting your preferred set of Policies.
For example, you may wish disable a certain set of Policies when
analyzing test programs. Conversely, you may wish to enable only a
specific subset of Policies when analyzing modules.
The Policies that ship with Perl::Critic are have been divided into the
following themes. This is just our attempt to provide some basic
logical groupings. You are free to invent new themes that suit your
needs.
THEME DESCRIPTION
------------------------------------------------------------------------
core All policies that ship with Perl::Critic
pbp Policies that come directly from "Perl Best Practices"
bugs Policies that that prevent or reveal bugs
certrec Policies that CERT recommends
certrule Policies that CERT considers rules
maintenance Policies that affect the long-term health of the code
cosmetic Policies that only have a superficial effect
complexity Policies that specificaly relate to code complexity
security Policies that relate to security issues
tests Policies that are specific to test programs
Say "perlcritic --list" to get a listing of all available policies and
the themes that are associated with each one. You can also change the
theme for any Policy in your .perlcriticrc file. See the
"CONFIGURATION" section for more information about that.
Using the "--theme" command-line option, you can create an arbitrarily
complex rule that determines which Policies to apply. Precedence is the
same as regular Perl code, and you can use parentheses to enforce
precedence as well. Supported operators are:
Operator Altertative Example
-----------------------------------------------------------------
&& and 'pbp && core'
|| or 'pbp || (bugs && security)'
! not 'pbp && ! (portability || complexity)'
Theme names are case-insensitive. If the "--theme" is set to an empty
string, then it evaluates as true all Policies.
BENDING THE RULES
Perl::Critic takes a hard-line approach to your code: either you comply
or you don't. In the real world, it is not always practical (or even
possible) to fully comply with coding standards. In such cases, it is
wise to show that you are knowingly violating the standards and that
you have a Damn Good Reason (DGR) for doing so.
To help with those situations, you can direct Perl::Critic to ignore
certain lines or blocks of code by using annotations:
require 'LegacyLibaray1.pl'; ## no critic
require 'LegacyLibrary2.pl'; ## no critic
for my $element (@list) {
## no critic
$foo = ""; #Violates 'ProhibitEmptyQuotes'
$barf = bar() if $foo; #Violates 'ProhibitPostfixControls'
#Some more evil code...
## use critic
#Some good code...
do_something($_);
}
The "## no critic" annotations direct Perl::Critic to ignore the
remaining lines of code until a "## use critic" annotation is found. If
the "## no critic" annotation is on the same line as a code statement,
then only that line of code is overlooked. To direct perlcritic to
ignore the "## no critic" annotations, use the "--force" option.
A bare "## no critic" annotation disables all the active Policies. If
you wish to disable only specific Policies, add a list of Policy names
as arguments just as you would for the "no strict" or "no warnings"
pragma. For example, this would disable the "ProhibitEmptyQuotes" and
"ProhibitPostfixControls" policies until the end of the block or until
the next "## use critic" annotation (whichever comes first):
## no critic (EmptyQuotes, PostfixControls);
# Now exempt from ValuesAndExpressions::ProhibitEmptyQuotes
$foo = "";
# Now exempt ControlStructures::ProhibitPostfixControls
$barf = bar() if $foo;
# Still subject to ValuesAndExpression::RequireNumberSeparators
$long_int = 10000000000;
Since the Policy names are matched against the "## no critic" arguments
as regular expressions, you can abbreviate the Policy names or disable
an entire family of Policies in one shot like this:
## no critic (NamingConventions)
# Now exempt from NamingConventions::Capitalization
my $camelHumpVar = 'foo';
# Now exempt from NamingConventions::Capitalization
sub camelHumpSub {}
The argument list must be enclosed in parentheses and must contain one
or more comma-separated barewords (i.e. don't use quotes). The "## no
critic" annotations can be nested, and Policies named by an inner
annotation will be disabled along with those already disabled an outer
annotation.
Some Policies like "Subroutines::ProhibitExcessComplexity" apply to an
entire block of code. In those cases, "## no critic" must appear on
the line where the violation is reported. For example:
sub complicated_function { ## no critic (ProhibitExcessComplexity)
# Your code here...
}
Some Policies like "Documentation::RequirePodSections" apply to the
entire document, in which case violations are reported at line 1. But
if the file requires a shebang line, it is impossible to put "## no
critic" on the first line of the file. This is a known limitation and
it will be addressed in a future release. As a workaround, you can
disable the affected policies at the command-line or in your
.perlcriticrc file. But beware that this will affect the analysis of
all files.
Use this feature wisely. "## no critic" should be used in the smallest
possible scope, or only on individual lines of code. And you should
always be as specific as possible about which policies you want to
disable (i.e. never use a bare "## no critic"). If Perl::Critic
complains about your code, try and find a compliant solution before
resorting to this feature.
EDITOR INTEGRATION
For ease-of-use, "perlcritic" can be integrated with your favorite text
editor. The output-formatting capabilities of "perlcritic" are
specifically intended for use with the "grep" or "compile" modes
available in editors like "emacs" and "vim". In these modes, you can
run an arbitrary command and the editor will parse the output into an
interactive buffer that you can click on and jump to the relevant line
of code.
The Perl::Critic team thanks everyone who has helped integrate Perl-
Critic with their favorite editor. Your contributions in particular
have made Perl- Critic a convenient and user-friendly tool for Perl
developers of all stripes. We sincerely appreciate your hard work.
EMACS
Joshua ben Jore has authored a minor-mode for emacs that allows you to
run perlcritic on the current region or buffer. You can run it on
demand, or configure it to run automatically when you save the buffer.
The output appears in a hot-linked compiler buffer. The code and
installation instructions can be found in the extras directory inside
this distribution.
VIM
Scott Peshak has published perlchecker.vim, which is available at
<http://www.vim.org/scripts/script.php?script_id=1731>.
gVIM
Fritz Mehner recently added support for "perlcritic" to his fantastic
gVIM plugin. In addition to providing a very Perlish IDE, Fritz's
plugin enables one-click access to "perlcritic" and many other very
useful utilities. And all is seamlessly integrated into the editor.
See <http://lug.fh-swf.de/vim/vim-perl/screenshots-en.html> for
complete details.
EPIC
EPIC is an open source Perl IDE based on the Eclipse platform. Features
include syntax highlighting, on-the-fly syntax check, content assist,
code completion, perldoc support, source formatting with Perl::Tidy,
code templates, a regular expression editing tool, and integration with
the Perl debugger. Recent versions of EPIC also have built-in support
for Perl::Critic. At least one Perl::Critic contributor swears by
EPIC. Go to <http://e-p-i-c.sourceforge.net> for more information
about EPIC.
BBEdit
Josh Clark has produced an excellent Perl-Critic plugin for BBEdit. See
<http://globalmoxie.com/projects/bbedit-perl-critic/index.shtml> for
download, installation, and usage instructions. Apple users rejoice!
Komodo
Komodo is a proprietary IDE for Perl and several other dynamic
languages. Starting in version 5.1.1, Komodo has built-in support for
Perl-Critic, if you have the Perl::Critic and criticism modules
installed. Free trial copies of Komodo can be obtained from the
ActiveState website at <http://www.activestate.com>.
ActivePerl
ActivePerl includes a very slick graphical interface for configuring
and running Perl-Critic called "perlcritic-gui". A free community
edition of ActivePerl can be obtained from the ActiveState website at
<http://www.activestate.com>.
EXIT STATUS
If "perlcritic" has any errors itself, exits with status == 1. If
there are no errors, but "perlcritic" finds Policy violations in your
source code, exits with status == 2. If there were no errors and no
violations were found, exits with status == 0.
THE Perl::Critic PHILOSOPHY
Coding standards are deeply personal and highly subjective. The
goal of Perl::Critic is to help you write code that conforms with a
set of best practices. Our primary goal is not to dictate what
those practices are, but rather, to implement the practices
discovered by others. Ultimately, you make the rules --
Perl::Critic is merely a tool for encouraging consistency. If
there is a policy that you think is important or that we have
overlooked, we would be very grateful for contributions, or you can
simply load your own private set of policies into Perl::Critic.
EXTENDING THE CRITIC
The modular design of Perl::Critic is intended to facilitate the
addition of new Policies. You'll need to have some understanding of
PPI, but most Policy modules are pretty straightforward and only
require about 20 lines of code. Please see the Perl::Critic::DEVELOPER
file included in this distribution for a step-by-step demonstration of
how to create new Policy modules.
If you develop any new Policy modules, feel free to send them to
"<team@perlcritic.com>" and I'll be happy to consider putting them into
the Perl::Critic distribution. Or if you would like to work on the
Perl::Critic project directly, you can fork our repository at
<https://github.com/Perl-Critic/Perl-Critic.git>.
The Perl::Critic team is also available for hire. If your organization
has its own coding standards, we can create custom Policies to enforce
your local guidelines. Or if your code base is prone to a particular
defect pattern, we can design Policies that will help you catch those
costly defects before they go into production. To discuss your needs
with the Perl::Critic team, just contact "<team@perlcritic.com>".
CONTACTING THE DEVELOPMENT TEAM
You are encouraged to subscribe to the mailing list at
<https://groups.google.com/d/forum/perl-critic>. At least one member
of the development team is usually hanging around in
<irc://irc.perl.org/#perlcritic> and you can follow Perl::Critic on
Twitter, at <https://twitter.com/perlcritic>.
SEE ALSO
There are a number of distributions of additional Policies available. A
few are listed here:
Perl::Critic::More(3)
Perl::Critic::Bangs(3)
Perl::Critic::Lax(3)
Perl::Critic::StricterSubs(3)
Perl::Critic::Swift(3)
Perl::Critic::Tics(3)
These distributions enable you to use Perl::Critic(3) in your unit
tests:
Test::Perl::Critic(3)
Test::Perl::Critic::Progressive(3)
There is also a distribution that will install all the Perl::Critic(3)
related modules known to the development team:
Task::Perl::Critic(3)
BUGS
Scrutinizing Perl code is hard for humans, let alone machines. If you
find any bugs, particularly false-positives or false-negatives from a
Perl::Critic::Policy, please submit them at
<https://github.com/Perl-Critic/Perl-Critic/issues>. Thanks.
CREDITS
Adam Kennedy - For creating PPI, the heart and soul of Perl::Critic.
Damian Conway - For writing Perl Best Practices, finally :)
Chris Dolan - For contributing the best features and Policy modules.
Andy Lester - Wise sage and master of all-things-testing.
Elliot Shank - The self-proclaimed quality freak.
Giuseppe Maxia - For all the great ideas and positive encouragement.
and Sharon, my wife - For putting up with my all-night code sessions.
Thanks also to the Perl Foundation for providing a grant to support
Chris Dolan's project to implement twenty PBP policies.
<http://www.perlfoundation.org/april_1_2007_new_grant_awards>
AUTHOR
Jeffrey Ryan Thalhammer <jeff@imaginative-software.com>
COPYRIGHT
Copyright (c) 2005-2011 Imaginative Software Systems. All rights
reserved.
This program is free software; you can redistribute it and/or modify it
under the same terms as Perl itself. The full text of this license can
be found in the LICENSE file included with this module.
perl v5.28.2 2019-05-24 perlcritic(1)
perl-critic 1.134.0 - Generated Sun Jun 2 09:19:38 CDT 2019