This module implements a subclass of Template::TT3::Element to represent various terminator tokens. It also acts as a base class for the Template::TT3::Element::End module.
Terminators are used to deliberately break the flow of the expression parser.
For example, the end token at the end of a template block is used to tell
the parse "Hey, stop that! We've run out of expressions. I'm special!".
Terminator tokens are also to indicate the end of data constructs such as
the ], } and ) tokens used for the end of list definitions, hash
definitions and parameter lists, respectively. Again, they are used as
hard markers to indicate the end of a sequence of expressions.
Terminator tokens are usually only ever consumed by the corresponding token
that began a block. For example, the [ token indicates the start of a list.
The
parse_expr()
method for
that element calls the
parse_body()
method on the next token. This will consume expressions until the next
terminator token and then return the block of expressions parsed. At this
point the $token reference will be pointing at the unconsumed terminator
token. The method can check that the terminator token is correct (e.g. is
] to match the opening [) and raise a syntax error if that is not the
case.
This module implements the following methods in addition to those inherited from the Template::TT3::Element , Template::TT3::Base and Badger::Base base classes.
This method returns undef to indicate that a delimiter element does not
yield an expression.
This method returns undef to indicate that a delimiter element does not
yield a body of expressions.
This method is an alias to the
reject()
method inherited from the
Template::TT3::Element
base class. It is called
by a preceding expression to give infix operators the opportunity to contribute
to expression generated. Terminators are mean old gits that don't like to
contribute anything, so they simply return the expression on the left of the
terminator, passed to the method as the $lhs argument.
An alias to the next_skip_ws() method inherited from Template::TT3::Element .
TODO: I don't think this is used any more.
This method is called by a
Template::TT3::View
object as part of the double
dispatch process that is used to render views of template elements. It calls
the view_terminator() method against the view object passed as the only
argument, $view. It passes itself as an argument to the
view_terminator() method.
Andy Wardley http://wardley.org
Copyright (C) 1996-2009 Andy Wardley. All Rights Reserved.
This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
This module inherits methods from the Template::TT3::Element , Template::TT3::Base and Badger::Base base classes.
It is constructed using the Template::TT3::Class::Element class metaprogramming module.
It is the base class for the Template::TT3::Element::End module.