NAME
Perl::Critic::Violation - A violation of a Policy found in some source code.
SYNOPSIS
use PPI;
use Perl::Critic::Violation;
my $elem = $doc->child(0);      # $doc is a PPI::Document object
my $desc = 'Offending code';    # Describe the violation
my $expl = [1,45,67];           # Page numbers from PBP
my $sev  = 5;                   # Severity level of this violation
my $vio  = Perl::Critic::Violation->new($desc, $expl, $node, $sev);
DESCRIPTION
Perl::Critic::Violation is the generic representation of an individual Policy violation. Its primary purpose is to provide an abstraction layer so that clients of Perl::Critic don't have to know anything about PPI. The violations method of all Perl::Critic::Policy subclasses must return a list of these Perl::Critic::Violation objects.
INTERFACE SUPPORT
This is considered to be a public class. Any changes to its interface will go through a deprecation cycle.
CONSTRUCTOR
new( $description, $explanation, $element, $severity )- 
Returns a reference to a new
Perl::Critic::Violationobject. The arguments are a description of the violation (as string), an explanation for the policy (as string) or a series of page numbers in PBP (as an ARRAY ref), a reference to the PPI element that caused the violation, and the severity of the violation (as an integer). 
METHODS
description()- 
Returns a brief description of the specific violation. In other words, this value may change on a per violation basis.
 explanation()- 
Returns an explanation of the policy as a string or as reference to an array of page numbers in PBP. This value will generally not change based upon the specific code violating the policy.
 location()- 
Don't use this method. Use the
line_number(),logical_line_number(),column_number(),visual_column_number(), andlogical_filename()methods instead.Returns a five-element array reference containing the line and real & virtual column and logical numbers and logical file name where this Violation occurred, as in PPI::Element.
 line_number()- 
Returns the physical line number that the violation was found on.
 logical_line_number()- 
Returns the logical line number that the violation was found on. This can differ from the physical line number when there were
#linedirectives in the code. column_number()- 
Returns the physical column that the violation was found at. This means that hard tab characters count as a single character.
 visual_column_number()- 
Returns the column that the violation was found at, as it would appear if hard tab characters were expanded, based upon the value of "tab_width [ $width ]" in PPI::Document.
 filename()- 
Returns the path to the file where this Violation occurred. In some cases, the path may be undefined because the source code was not read directly from a file.
 logical_filename()- 
Returns the logical path to the file where the Violation occurred. This can differ from
filename()when there was a#linedirective in the code. severity()- 
Returns the severity of this Violation as an integer ranging from 1 to 5, where 5 is the "most" severe.
 sort_by_severity( @violation_objects )- 
If you need to sort Violations by severity, use this handy routine:
@sorted = Perl::Critic::Violation::sort_by_severity(@violations); sort_by_location( @violation_objects )- 
If you need to sort Violations by location, use this handy routine:
@sorted = Perl::Critic::Violation::sort_by_location(@violations); diagnostics()- 
Returns a formatted string containing a full discussion of the motivation for and details of the Policy module that created this Violation. This information is automatically extracted from the
DESCRIPTIONsection of the Policy module's POD. policy()- 
Returns the name of the Perl::Critic::Policy that created this Violation.
 source()- 
Returns the string of source code that caused this exception. If the code spans multiple lines (e.g. multi-line statements, subroutines or other blocks), then only the line containing the violation will be returned.
 element_class()- 
Returns the PPI::Element subclass of the code that caused this exception.
 set_format( $format )- 
Class method. Sets the format for all Violation objects when they are evaluated in string context. The default is
'%d at line %l, column %c. %e'. See "OVERLOADS" for formatting options. get_format()- 
Class method. Returns the current format for all Violation objects when they are evaluated in string context.
 to_string()- 
Returns a string representation of this violation. The content of the string depends on the current value of the
$formatpackage variable. See "OVERLOADS" for the details. 
OVERLOADS
Perl::Critic::Violation overloads the "" operator to produce neat little messages when evaluated in string context.
Formats are a combination of literal and escape characters similar to the way sprintf works. If you want to know the specific formatting capabilities, look at String::Format. Valid escape characters are:
Escape    Meaning
-------   ----------------------------------------------------------------
%c        Column number where the violation occurred
%d        Full diagnostic discussion of the violation (DESCRIPTION in POD)
%e        Explanation of violation or page numbers in PBP
%F        Just the name of the logical file where the violation occurred.
%f        Path to the logical file where the violation occurred.
%G        Just the name of the physical file where the violation occurred.
%g        Path to the physical file where the violation occurred.
%l        Logical line number where the violation occurred
%L        Physical 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
Explanation of the %F, %f, %G, %G, %l, and %L formats: Using #line directives, you can affect what perl thinks the current line number and file name are; see "Plain Old Comments (Not!)" in perlsyn for the details. Under normal circumstances, the values of %F, %f, and %l will match the values of %G, %g, and %L, respectively. In the presence of a #line directive, the values of %F, %f, and %l will change to take that directive into account. The values of %G, %g, and %L are unaffected by those directives.
Here are some examples:
Perl::Critic::Violation::set_format("%m at line %l, column %c.\n");
# looks like "Mixed case variable name at line 6, column 23."
Perl::Critic::Violation::set_format("%m near '%r'\n");
# looks like "Mixed case variable name near 'my $theGreatAnswer = 42;'"
Perl::Critic::Violation::set_format("%l:%c:%p\n");
# looks like "6:23:NamingConventions::Capitalization"
Perl::Critic::Violation::set_format("%m at line %l. %e. \n%d\n");
# looks like "Mixed case variable name at line 6.  See page 44 of PBP.
  Conway's recommended naming convention is to use lower-case words
  separated by underscores.  Well-recognized acronyms can be in ALL
  CAPS, but must be separated by underscores from other parts of the
  name."
AUTHOR
Jeffrey Ryan Thalhammer <jeff@imaginative-software.com>
COPYRIGHT
Copyright (c) 2005-2023 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.