Perl::Critic::Utils(3)User Contributed Perl DocumentatioPerl::Critic::Utils(3)NAMEPerl::Critic::Utils - General utility subroutines and constants for
Perl::Critic and derivative distributions.
DESCRIPTION
This module provides several static subs and variables that are useful
for developing Perl::Critic::Policy subclasses. Unless you are writing
Policy modules, you probably don't care about this package.
INTERFACE SUPPORT
This is considered to be a public module. Any changes to its interface
will go through a deprecation cycle.
IMPORTABLE SUBS
"find_keywords( $doc, $keyword )"
DEPRECATED: Since version 0.11, every Policy is evaluated at each
element of the document. So you shouldn't need to go looking for a
particular keyword. If you do want to use this, please import it
via the ":deprecated" tag, rather than directly, to mark the module
as needing updating.
Given a PPI::Document as $doc, returns a reference to an array
containing all the PPI::Token::Word elements that match $keyword.
This can be used to find any built-in function, method call,
bareword, or reserved keyword. It will not match variables,
subroutine names, literal strings, numbers, or symbols. If the
document doesn't contain any matches, returns undef.
"is_perl_global( $element )"
Given a PPI::Token::Symbol or a string, returns true if that token
represents one of the global variables provided by the English
module, or one of the builtin global variables like %SIG, %ENV, or
@ARGV. The sigil on the symbol is ignored, so things like $ARGV or
$ENV will still return true.
"is_perl_builtin( $element )"
Given a PPI::Token::Word, PPI::Statement::Sub, or string, returns
true if that token represents a call to any of the builtin
functions defined in Perl 5.8.8.
"is_perl_bareword( $element )"
Given a PPI::Token::Word, PPI::Statement::Sub, or string, returns
true if that token represents a bareword (e.g. "if", "else", "sub",
"package") defined in Perl 5.8.8.
"is_perl_filehandle( $element )"
Given a PPI::Token::Word, or string, returns true if that token
represents one of the global filehandles (e.g. "STDIN", "STDERR",
"STDOUT", "ARGV") that are defined in Perl 5.8.8. Note that this
function will return false if given a filehandle that is
represented as a typeglob (e.g. *STDIN)
"is_perl_builtin_with_list_context( $element )"
Given a PPI::Token::Word, PPI::Statement::Sub, or string, returns
true if that token represents a call to any of the builtin
functions defined in Perl 5.8.8 that provide a list context to the
following tokens.
"is_perl_builtin_with_multiple_arguments( $element )"
Given a PPI::Token::Word, PPI::Statement::Sub, or string, returns
true if that token represents a call to any of the builtin
functions defined in Perl 5.8.8 that can take multiple arguments.
"is_perl_builtin_with_no_arguments( $element )"
Given a PPI::Token::Word, PPI::Statement::Sub, or string, returns
true if that token represents a call to any of the builtin
functions defined in Perl 5.8.8 that cannot take any arguments.
"is_perl_builtin_with_one_argument( $element )"
Given a PPI::Token::Word, PPI::Statement::Sub, or string, returns
true if that token represents a call to any of the builtin
functions defined in Perl 5.8.8 that takes one and only one
argument.
"is_perl_builtin_with_optional_argument( $element )"
Given a PPI::Token::Word, PPI::Statement::Sub, or string, returns
true if that token represents a call to any of the builtin
functions defined in Perl 5.8.8 that takes no more than one
argument.
The sets of values for which
"is_perl_builtin_with_multiple_arguments()",
"is_perl_builtin_with_no_arguments()",
"is_perl_builtin_with_one_argument()", and
"is_perl_builtin_with_optional_argument()" return true are disjoint
and their union is precisely the set of values that
"is_perl_builtin()" will return true for.
"is_perl_builtin_with_zero_and_or_one_arguments( $element )"
Given a PPI::Token::Word, PPI::Statement::Sub, or string, returns
true if that token represents a call to any of the builtin
functions defined in Perl 5.8.8 that takes no and/or one argument.
Returns true if any of "is_perl_builtin_with_no_arguments()",
"is_perl_builtin_with_one_argument()", and
"is_perl_builtin_with_optional_argument()" returns true.
"is_qualified_name( $name )"
Given a string, PPI::Token::Word, or PPI::Token::Symbol, answers
whether it has a module component, i.e. contains "::".
"precedence_of( $element )"
Given a PPI::Token::Operator or a string, returns the precedence of
the operator, where 1 is the highest precedence. Returns undef if
the precedence can't be determined (which is usually because it is
not an operator).
"is_hash_key( $element )"
Given a PPI::Element, returns true if the element is a literal hash
key. PPI doesn't distinguish between regular barewords (like
keywords or subroutine calls) and barewords in hash subscripts
(which are considered literal). So this subroutine is useful if
your Policy is searching for PPI::Token::Word elements and you want
to filter out the hash subscript variety. In both of the following
examples, "foo" is considered a hash key:
$hash1{foo} = 1;
%hash2 = (foo => 1);
But if the bareword is followed by an argument list, then perl
treats it as a function call. So in these examples, "foo" is not
considered a hash key:
$hash1{ foo() } = 1;
&hash2 = (foo() => 1);
"is_included_module_name( $element )"
Given a PPI::Token::Word, returns true if the element is the name
of a module that is being included via "use", "require", or "no".
"is_integer( $value )"
Answers whether the parameter, as a string, looks like an integral
value.
"is_class_name( $element )"
Given a PPI::Token::Word, returns true if the element that
immediately follows this element is the dereference operator "->".
When a bareword has a "->" on the right side, it usually means that
it is the name of the class (from which a method is being called).
"is_label_pointer( $element )"
Given a PPI::Token::Word, returns true if the element is the label
in a "next", "last", "redo", or "goto" statement. Note this is not
the same thing as the label declaration.
"is_method_call( $element )"
Given a PPI::Token::Word, returns true if the element that
immediately precedes this element is the dereference operator "->".
When a bareword has a "->" on the left side, it usually means that
it is the name of a method (that is being called from a class).
"is_package_declaration( $element )"
Given a PPI::Token::Word, returns true if the element is the name
of a package that is being declared.
"is_subroutine_name( $element )"
Given a PPI::Token::Word, returns true if the element is the name
of a subroutine declaration. This is useful for distinguishing
barewords and from function calls from subroutine declarations.
"is_function_call( $element )"
Given a PPI::Token::Word returns true if the element appears to be
call to a static function. Specifically, this function returns
true if "is_hash_key", "is_method_call", "is_subroutine_name",
"is_included_module_name", "is_package_declaration",
"is_perl_bareword", "is_perl_filehandle", "is_label_pointer" and
"is_subroutine_name" all return false for the given element.
"first_arg( $element )"
Given a PPI::Element that is presumed to be a function call (which
is usually a PPI::Token::Word), return the first argument. This is
similar of "parse_arg_list()" and follows the same logic. Note
that for the code:
int($x + 0.5)
this function will return just the $x, not the whole expression.
This is different from the behavior of "parse_arg_list()". Another
caveat is:
int(($x + $y) + 0.5)
which returns "($x + $y)" as a PPI::Structure::List instance.
"parse_arg_list( $element )"
Given a PPI::Element that is presumed to be a function call (which
is usually a PPI::Token::Word), splits the argument expressions
into arrays of tokens. Returns a list containing references to
each of those arrays. This is useful because parentheses are
optional when calling a function, and PPI parses them very
differently. So this method is a poor-man's parse tree of PPI
nodes. It's not bullet-proof because it doesn't respect
precedence. In general, I don't like the way this function works,
so don't count on it to be stable (or even present).
"split_nodes_on_comma( @nodes )"
This has the same return type as "parse_arg_list()" but expects to
be passed the nodes that represent the interior of a list, like:
'foo', 1, 2, 'bar'
"is_script( $document )"
This subroutine is deprecated and will be removed in a future
release. You should use the "is_program()" in
Perl::Critic::Document method instead.
"is_in_void_context( $token )"
Given a PPI::Token, answer whether it appears to be in a void
context.
"policy_long_name( $policy_name )"
Given a policy class name in long or short form, return the long
form.
"policy_short_name( $policy_name )"
Given a policy class name in long or short form, return the short
form.
"all_perl_files( @directories )"
Given a list of directories, recursively searches through all the
directories (depth first) and returns a list of paths for all the
files that are Perl code files. Any administrative files for CVS
or Subversion are skipped, as are things that look like temporary
or backup files.
A Perl code file is:
· Any file that ends in .PL, .pl, .pm, or .t
· Any file that has a first line with a shebang containing 'perl'
"severity_to_number( $severity )"
If $severity is given as an integer, this function returns
$severity but normalized to lie between $SEVERITY_LOWEST and
$SEVERITY_HIGHEST. If $severity is given as a string, this
function returns the corresponding severity number. If the string
doesn't have a corresponding number, this function will throw an
exception.
"is_valid_numeric_verbosity( $severity )"
Answers whether the argument has a translation to a Violation
format.
"verbosity_to_format( $verbosity_level )"
Given a verbosity level between 1 and 10, returns the corresponding
predefined format string. These formats are suitable for passing
to the "set_format" method in Perl::Critic::Violation. See the
perlcritic documentation for a listing of the predefined formats.
"hashify( @list )"
Given @list, return a hash where @list is in the keys and each
value is 1. Duplicate values in @list are silently squished.
"interpolate( $literal )"
Given a $literal string that may contain control characters (e.g..
'\t' '\n'), this function does a double interpolation on the string
and returns it as if it had been declared in double quotes. For
example:
'foo \t bar \n' ...becomes... "foo \t bar \n"
"shebang_line( $document )"
Given a PPI::Document, test if it starts with "#!". If so, return
that line. Otherwise return undef.
"words_from_string( $str )"
Given config string $str, return all the words from the string.
This is safer than splitting on whitespace.
"is_unchecked_call( $element )"
Given a PPI::Element, test to see if it contains a function call
whose return value is not checked.
IMPORTABLE VARIABLES
$COMMA
$FATCOMMA
$COLON
$SCOLON
$QUOTE
$DQUOTE
$BACKTICK
$PERIOD
$PIPE
$EMPTY
$EQUAL
$SPACE
$SLASH
$BSLASH
$LEFT_PAREN
$RIGHT_PAREN
These character constants give clear names to commonly-used strings
that can be hard to read when surrounded by quotes and other
punctuation. Can be imported in one go via the ":characters" tag.
$SEVERITY_HIGHEST
$SEVERITY_HIGH
$SEVERITY_MEDIUM
$SEVERITY_LOW
$SEVERITY_LOWEST
These numeric constants define the relative severity of violating
each Perl::Critic::Policy. The "get_severity" and
"default_severity" methods of every Policy subclass must return one
of these values. Can be imported via the ":severities" tag.
$DEFAULT_VERBOSITY
The default numeric verbosity.
$DEFAULT_VERBOSITY_WITH_FILE_NAME
The numeric verbosity that corresponds to the format indicated by
$DEFAULT_VERBOSITY, but with the file name prefixed to it.
$TRUE
$FALSE
These are simple booleans. 1 and 0 respectively. Be mindful of
using these with string equality. "$FALSE ne $EMPTY". Can be
imported via the ":booleans" tag.
IMPORT TAGS
The following groups of functions and constants are available as
parameters to a "use Perl::Critic::Util" statement.
":all"
The lot.
":booleans"
Includes: $TRUE, $FALSE
":severities"
Includes: $SEVERITY_HIGHEST, $SEVERITY_HIGH, $SEVERITY_MEDIUM,
$SEVERITY_LOW, $SEVERITY_LOWEST, @SEVERITY_NAMES
":characters"
Includes: $COLON, $COMMA, $DQUOTE, $EMPTY, $FATCOMMA, $PERIOD,
$PIPE, $QUOTE, $BACKTICK, $SCOLON, $SPACE, $SLASH, $BSLASH
$LEFT_PAREN $RIGHT_PAREN
":classification"
Includes: "is_function_call", "is_hash_key",
"is_included_module_name", "is_integer", "is_method_call",
"is_package_declaration", "is_perl_builtin", "is_perl_global",
"is_perl_builtin_with_list_context"
"is_perl_builtin_with_multiple_arguments"
"is_perl_builtin_with_no_arguments"
"is_perl_builtin_with_one_argument"
"is_perl_builtin_with_optional_argument"
"is_perl_builtin_with_zero_and_or_one_arguments" "is_script",
"is_subroutine_name", "is_unchecked_call"
"is_valid_numeric_verbosity"
See also Perl::Critic::Utils::PPI.
":data_conversion"
Generic manipulation, not having anything specific to do with
Perl::Critic.
Includes: "hashify", "words_from_string", "interpolate"
":ppi"
Things for dealing with PPI, other than classification.
Includes: "first_arg", "parse_arg_list"
See also Perl::Critic::Utils::PPI.
":internal_lookup"
Translations between internal representations.
Includes: "severity_to_number", "verbosity_to_format"
":language"
Information about Perl not programmatically available elsewhere.
Includes: "precedence_of"
":deprecated"
Not surprisingly, things that are deprecated. It is preferred to
use this tag to get to these functions, rather than the function
names themselves, so as to mark any module using them as needing
cleanup.
Includes: "find_keywords"
SEE ALSO
Perl::Critic::Utils::Constants, Perl::Critic::Utils::McCabe,
Perl::Critic::Utils::PPI,
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 v5.14.1 2011-07-22 Perl::Critic::Utils(3)
