NAME

Text::MicroMason::Filters - Filter output with "|h" and "|u"

SYNOPSIS

Instead of using this class directly, pass its name to be mixed in:

    use Text::MicroMason;
    my $mason = Text::MicroMason->new( -Filters );

Enables filtering of template expressions using HTML::Mason's conventions:

    <%args> $name </%args>
    Welcome, <% $name |h %>! 
    <a href="more.masn?name=<% $name |u %>">Click for More</a>

You can set a default filter and override it with the "n" flag:

    my $mason = Text::MicroMason->new( -Filters, default_filters => 'h' );

    <%args> $name </%args>
    Welcome, <% $name %>! 
    <a href="more.masn?name=<% $name |nu %>">Click for More</a>

You can define additional filters and stack them:

    my $mason = Text::MicroMason->new( -Filters );
    $mason->filter_functions( myfilter => \&function );
    $mason->filter_functions( uc => sub { return uc( shift ) } );

    <%args> $name </%args>
    Welcome, <% $name |uc,myfilter %>! 

DESCRIPTION

This module enables the filtering of expressions before they are output, using HTML::Mason's "|hun" syntax.

If you have HTML::Entities and URI::Escape available they are loaded to provide the default "h" and "u" filters. If those modules can not be loaded, no error message is produced but any subsequent use of them will fail with a message stating "No definition for a filter named 'h'".

Public Methods

filter_functions

Gets and sets values from the hash mapping filter flags to functions.

If called with no arguments, returns a hash of all available filter flags and functions:

  %functions = $mason->filter_functions();

If called with a filter flag returns the associated function, or if provided with a reference to an array of flag names returns a list of the functions:

  $function  = $mason->filter_functions( $flag );
  @functions = $mason->filter_functions( \@flags );

If called with one or more pairs of filter flags and associated functions, adds them to the hash. (Any filter that might have existed with the same flag name is overwritten.)

  $mason->filter_functions( $flag => $function, ... );

parse_filters

Parses one or more strings containing any number of filter flags and returns a list of flags to be used.

  @flags = $mason->parse_filters( @filter_strings );

Flags should be separated by commas, except that the commas may be omitted when using only the built-in "h", "u" and "n" flags. Flags are applied from left to right. Any use of the "n" flag wipes out all flags defined to the left of it.

filter

Applies one or more filters to the provided content string.

  $result = $mason->filter( @filters, $content );

Supported Attributes

default_filters

Optional comma-separated string of filter flags to be applied to all output expressions unless overridden by the "n" flag.

Private Methods

assemble()

This method goes through the lexed template tokens looking for uses of filter flags, which it then rewrites as appropriate method calls before passing the tokens on to the superclass.

SEE ALSO

For the core functionality of this package see Text::MicroMason and Text::MicroMason::Base.

For distribution, installation, support, copyright and license information, see Text::MicroMason::ReadMe.