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PPI::Statement(3)                    User Contributed Perl Documentation                   PPI::Statement(3)



NAME
       PPI::Statement - The base class for Perl statements

INHERITANCE
         PPI::Statement
         isa PPI::Node
             isa PPI::Element

DESCRIPTION
       PPI::Statement is the root class for all Perl statements. This includes (from perlsyn)
       "Declarations", "Simple Statements" and "Compound Statements".

       The class PPI::Statement itself represents a "Simple Statement" as defined in the perlsyn manpage.

STATEMENT CLASSES
       Please note that unless documented themselves, these classes are yet to be frozen/finalised. Names
       may change slightly or be added or removed.

   PPI::Statement::Scheduled
       This covers all "scheduled" blocks, chunks of code that are executed separately from the main body of
       the code, at a particular time. This includes all "BEGIN", "CHECK", "UNITCHECK", "INIT" and "END"
       blocks.

   PPI::Statement::Package
       A package declaration, as defined in perlfunc.

   PPI::Statement::Include
       A statement that loads or unloads another module.

       This includes 'use', 'no', and 'require' statements.

   PPI::Statement::Sub
       A named subroutine declaration, or forward declaration

   PPI::Statement::Variable
       A variable declaration statement. This could be either a straight declaration or also be an
       expression.

       This includes all 'my', 'state', 'local' and 'our' statements.

   PPI::Statement::Compound
       This covers the whole family of 'compound' statements, as described in perlsyn.

       This includes all statements starting with 'if', 'unless', 'for', 'foreach' and 'while'. Note that
       this does NOT include 'do', as it is treated differently.

       All compound statements have implicit ends. That is, they do not end with a ';' statement terminator.

   PPI::Statement::Break
       A statement that breaks out of a structure.

       This includes all of 'redo', 'next', 'last' and 'return' statements.

   PPI::Statement::Given
       The kind of statement introduced in Perl 5.10 that starts with 'given'.  This has an implicit end.

   PPI::Statement::When
       The kind of statement introduced in Perl 5.10 that starts with 'when' or 'default'.  This also has an
       implicit end.

   PPI::Statement::Data
       A special statement which encompasses an entire "__DATA__" block, including the initial '__DATA__'
       token itself and the entire contents.

   PPI::Statement::End
       A special statement which encompasses an entire __END__ block, including the initial '__END__' token
       itself and the entire contents, including any parsed PPI::Token::POD that may occur in it.

   PPI::Statement::Expression
       PPI::Statement::Expression is a little more speculative, and is intended to help represent the
       special rules relating to "expressions" such as in:

         # Several examples of expression statements

         # Boolean conditions
         if ( expression ) { ... }

         # Lists, such as for arguments
         Foo->bar( expression )

   PPI::Statement::Null
       A null statement is a special case for where we encounter two consecutive statement terminators. ( ;;
       )

       The second terminator is given an entire statement of its own, but one that serves no purpose. Hence
       a 'null' statement.

       Theoretically, assuming a correct parsing of a perl file, all null statements are superfluous and
       should be able to be removed without damage to the file.

       But don't do that, in case PPI has parsed something wrong.

   PPI::Statement::UnmatchedBrace
       Because PPI is intended for use when parsing incorrect or incomplete code, the problem arises of what
       to do with a stray closing brace.

       Rather than die, it is allocated its own "unmatched brace" statement, which really means "unmatched
       closing brace". An unmatched open brace at the end of a file would become a structure with no
       contents and no closing brace.

       If the document loaded is intended to be correct and valid, finding a PPI::Statement::UnmatchedBrace
       in the PDOM is generally indicative of a misparse.

   PPI::Statement::Unknown
       This is used temporarily mid-parsing to hold statements for which the lexer cannot yet determine what
       class it should be, usually because there are insufficient clues, or it might be more than one thing.

       You should never encounter these in a fully parsed PDOM tree.

METHODS
       "PPI::Statement" itself has very few methods. Most of the time, you will be working with the more
       generic PPI::Element or PPI::Node methods, or one of the methods that are subclass-specific.

   label
       One factor common to most statements is their ability to be labeled.

       The "label" method returns the label for a statement, if one has been defined, but without the
       trailing colon. Take the following example

         MYLABEL: while ( 1 .. 10 ) { last MYLABEL if $_ > 5 }

       For the above statement, the "label" method would return 'MYLABEL'.

       Returns false if the statement does not have a label.

   specialized
       Answer whether this is a plain statement or one that has more significance.

       Returns true if the statement is a subclass of this one, false otherwise.

   stable
       Much like the PPI::Document method of the same name, the ->stable method converts a statement to
       source and back again, to determine if a modified statement is still legal, and won't be interpreted
       in a different way.

       Returns true if the statement is stable, false if not, or "undef" on error.

TO DO
       - Complete, freeze and document the remaining classes

SUPPORT
       See the support section in the main module.

AUTHOR
       Adam Kennedy <adamk@cpan.org>

COPYRIGHT
       Copyright 2001 - 2011 Adam Kennedy.

       This program is free software; you can redistribute it and/or modify it under the same terms as Perl
       itself.

       The full text of the license can be found in the LICENSE file included with this module.



perl v5.12.5                                     2011-02-25                                PPI::Statement(3)