bionic (3) PPIx::Regexp::Element.3pm.gz

NAME

       PPIx::Regexp::Element - Base of the PPIx::Regexp hierarchy.

SYNOPSIS

       No user-serviceable parts inside.

INHERITANCE

       "PPIx::Regexp::Element" is not descended from any other class.

       "PPIx::Regexp::Element" is the parent of PPIx::Regexp::Node and PPIx::Regexp::Token.

DESCRIPTION

       This class is the base of the PPIx::Regexp object hierarchy. It provides the same kind of navigational
       functionality that is provided by PPI::Element.

METHODS

       This class provides the following public methods. Methods not documented here are private, and
       unsupported in the sense that the author reserves the right to change or remove them without notice.

   accepts_perl
        $token->accepts_perl( '5.020' )
            and say 'This works under Perl 5.20';

       This method returns a true value if the token is acceptable under the specified version of Perl, and a
       false value otherwise. Unless the token (or its contents) have been equivocated on, the result is simply
       what you would expect based on testing the results of perl_version_introduced() and
       perl_version_removed() versus the given Perl version number.

       This method was added in version 0.051_01.

   ancestor_of
       This method returns true if the object is an ancestor of the argument, and false otherwise. By the
       definition of this method, $self is its own ancestor.

   can_be_quantified
        $token->can_be_quantified()
            and print "This element can be quantified.\n";

       This method returns true if the element can be quantified.

   class
       This method returns the class name of the element. It is the same as "ref $self".

   comment
       This method returns true if the element is a comment and false otherwise.

   content
       This method returns the content of the element.

   descendant_of
       This method returns true if the object is a descendant of the argument, and false otherwise. By the
       definition of this method, $self is its own descendant.

   explain
       This method returns a brief explanation of what the element does. The return will be either a string or
       "undef" in scalar context, but may be multiple values or an empty array in list context.

       This method should be considered experimental. What it returns may change without notice as my
       understanding of what all the pieces/parts of a Perl regular expression evolves. The worst case is that
       it will prove entirely infeasible to implement satisfactorily, in which case it will be put through a
       deprecation cycle and retracted.

   error
        say $token->error();

       If an element is one of the classes that represents a parse error, this method may return a brief message
       saying why. Otherwise it will return "undef".

   in_regex_set
       This method returns a true value if the invocant is contained in an extended bracketed character class
       (also known as a regex set), and a false value otherwise. This method returns true if the invocant is a
       PPIx::Regexp::Structure::RegexSet.

   is_quantifier
        $token->is_quantifier()
            and print "This element is a quantifier.\n";

       This method returns true if the element is a quantifier. You can not tell this from the element's class,
       because a right curly bracket may represent a quantifier for the purposes of figuring out whether a
       greediness token is possible.

   main_structure
       This method returns the PPIx::Regexp::Structure::Main that contains the element. In practice this will be
       a PPIx::Regexp::Structure::Regexp or a PPIx::Regexp::Structure::Replacement,

       If the element is not contained in any such structure, "undef" is returned. This will happen if the
       element is a PPIx::Regexp or one of its immediate children.

   modifier_asserted
        $token->modifier_asserted( 'i' )
            and print "Matched without regard to case.\n";

       This method returns true if the given modifier is in effect for the element, and false otherwise.

       What it does is to walk backwards from the element until it finds a modifier object that specifies the
       modifier, whether asserted or negated. and returns the specified value. If nobody specifies the modifier,
       it returns "undef".

       This method will not work reliably if called on tokenizer output.

   next_sibling
       This method returns the element's next sibling, or nothing if there is none.

   parent
       This method returns the parent of the element, or undef if there is none.

   perl_version_introduced
       This method returns the version of Perl in which the element was introduced. This will be at least 5.000.
       Before 5.006 I am relying on the perldelta, perlre, and perlop documentation, since I have been unable to
       build earlier Perls. Since I have found no documentation before 5.003, I assume that anything found in
       5.003 is also in 5.000.

       Since this all depends on my ability to read and understand masses of documentation, the results of this
       method should be viewed with caution, if not downright skepticism.

       There are also cases which are ambiguous in various ways. For those see the PPIx::Regexp documentation,
       particularly Changes in Syntax.

       Very occasionally, a construct will be removed and then added back. If this happens, this method will
       return the lowest version in which the construct appeared. For the known instances of this, see the
       PPIx::Regexp documentation, particularly Equivocation.

   perl_version_removed
       This method returns the version of Perl in which the element was removed. If the element is still valid
       the return is "undef".

       All the caveats to perl_version_introduced() apply here also, though perhaps less severely since although
       many features have been introduced since 5.0, few have been removed.

       Very occasionally, a construct will be removed and then added back. If this happens, this method will
       return the "undef" if the construct is present in the highest-numbered version of Perl (whether
       production or development), or the version after the highest-numbered version in which it appeared
       otherwise. For the known instances of this, see the PPIx::Regexp documentation, particularly
       Equivocation.

   previous_sibling
       This method returns the element's previous sibling, or nothing if there is none.

   requirements_for_perl
        say $token->requirements_for_perl();

       This method returns a string representing the Perl requirements for a given module. This should only be
       used for informational purposes, as the format of the string may be subject to change.

       This method was added in version 0.051_01.

   scontent
       This method returns the significant content of the element. That is, if called on the parse of '/ f u b a
       r /x', it returns '/fubar/x'. If the invocant contains no insignificant elements, it is the same as
       content(). If called on an insignificant element, it returns nothing -- that is, "undef" in scalar
       context, and an empty list in list context.

       This method was inspired by jb's question on Perl Monks about stripping comments and white space from a
       regular expression: <http://www.perlmonks.org/?node_id=1207556>

       This method was added in version 0.053_01

   significant
       This method returns true if the element is significant and false otherwise.

   snext_sibling
       This method returns the element's next significant sibling, or nothing if there is none.

   sprevious_sibling
       This method returns the element's previous significant sibling, or nothing if there is none.

   tokens
       This method returns all tokens contained in the element.

   top
       This method returns the top of the hierarchy.

   unescaped_content
       This method returns the content of the element, unescaped.

   whitespace
       This method returns true if the element is whitespace and false otherwise.

   nav
       This method returns navigation information from the top of the hierarchy to this node. The return is a
       list of names of methods and references to their argument lists. The idea is that given $elem which is
       somewhere under $top,

        my @nav = $elem->nav();
        my $obj = $top;
        while ( @nav ) {
            my $method = shift @nav;
            my $args = shift @nav;
            $obj = $obj->$method( @{ $args } ) or die;
        }
        # At this point, $obj should contain the same object
        # as $elem.

SUPPORT

       Support is by the author. Please file bug reports at <http://rt.cpan.org>, or in electronic mail to the
       author.

AUTHOR

       Thomas R. Wyant, III wyant at cpan dot org

COPYRIGHT AND LICENSE

       Copyright (C) 2009-2018 by Thomas R. Wyant, III

       This program is free software; you can redistribute it and/or modify it under the same terms as Perl
       5.10.0. For more details, see the full text of the licenses in the directory LICENSES.

       This program is distributed in the hope that it will be useful, but without any warranty; without even
       the implied warranty of merchantability or fitness for a particular purpose.