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', 'goto', '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.