Template::Alloy::Parse 1.006

Template::Alloy::Parse is a Perl module with common parsing role for creating AST from templates.

The Template::Alloy::Parse role is reponsible for storing the majority of directive parsing code, as well as for delegating to the TT, HTE, Tmpl, and Velocity roles for finding variables and directives.

ROLE METHODS

parse_tree

Used by load_tree. This is the main grammar engine of the program. It delegates to the syntax found in $self->{SYNTAX} (defaults to alloy) and calls the function found in the $SYNTAX hashref. The majority of these syntaxes use methods found in the $DIRECTIVES hashref to parse different DIRECTIVE types for each particular syntax.

A template that looked like the following:

Foo
[%- GET foo -%]
[%- GET bar -%]
Bar

would parse to the following AST:

[
Foo,
[GET, 6, 15, [foo, 0]],
[GET, 22, 31, [bar, 0]],
Bar,
]

The "GET" words represent the directive used. The 6, 15 represent the beginning and ending characters of the directive in the document. The remaining items are the variables necessary for running the particular directive.
parse_expr

Used to parse a variable, an expression, a literal string, or a number. It returns a parsed variable tree. Samples of parsed variables can be found in the VARIABLE PARSE TREE section.

my $str = "1 + 2 * 3";
my $ast = $self->parse_expr($str);
# $ast looks like [[undef, +, 1, [[undef, *, 2, 3], 0]], 0]
parse_args

Allow for the multitudinous ways that TT parses arguments. This allows for positional as well as named arguments. Named arguments can be separated with a "=" or "=>", and positional arguments should be separated by " " or ",". This only returns an array of parsed variables. To get the actual values, you must call play_expr on each value.

dump_parse_tree

This method allows for returning a string of perl code representing the AST of the parsed tree.

It is mainly used for testing.

dump_parse_expr

This method allows for returning a Data::Dumper dump of a parsed variable. It is mainly used for testing.

parse_*

Methods by these names are used by parse_tree to parse the template. These are the grammar. They are used by all of the various template syntaxes Unless otherwise mentioned, these methods are not exposed via the role.