NAME¶
Text::MicroMason::Functions - Function Exporter for Simple Mason Templates
SYNOPSIS¶
Use the execute function to parse and evalute a template:
use Text::MicroMason::Functions qw( execute );
print execute($template, 'name'=>'Dave');
Or compile it into a subroutine, and evaluate repeatedly:
use Text::MicroMason::Functions qw( compile );
$coderef = compile($template);
print $coderef->('name'=>'Dave');
print $coderef->('name'=>'Bob');
Templates stored in files can be run directly or included in others:
use Text::MicroMason::Functions qw( execute_file );
print execute_file( "./greeting.msn", 'name'=>'Charles');
Safe usage restricts templates from accessing your files or data:
use Text::MicroMason::Functions qw( safe_execute );
print safe_execute( $template, 'name'=>'Bob');
All above functions are available in an error-catching "try_*" form:
use Text::MicroMason::Functions qw( try_execute );
($result, $error) = try_execute( $template, 'name'=>'Alice');
DESCRIPTION¶
As an alternative to the object-oriented interface, text containing MicroMason
markup code can be compiled and executed by calling the following functions.
Please note that this interface is maintained primarily for backward
compatibility with version 1 of Text::MicroMason, and it does not provide
access to some of the newer features.
Each function creates a new MicroMason object, including any necessary traits
such as Safe compilation or CatchErrors for exceptions, and then passes its
arguments to an appropriate method on that object.
You may import any of these functions by including their names in your "use
Text::MicroMason" statement.
Basic Invocation¶
To evaluate a Mason-like template, pass it to
execute():
$result = execute( $mason_text );
Alternately, you can call
compile() to generate a subroutine for your
template, and then run the subroutine:
$result = compile( $mason_text )->();
If you will be interpreting the same template repeatedly, you can save the
compiled version for faster execution:
$sub_ref = compile( $mason_text );
$result = $sub_ref->();
(Note that the $sub_ref->() syntax is unavailable in older versions of Perl;
use the equivalent &$
sub_ref() syntax instead.)
Argument Passing¶
You can also pass a list of key-value pairs as arguments to execute, or to the
compiled subroutine:
$result = execute( $mason_text, %args );
$result = $sub_ref->( %args );
Within the scope of your template, any arguments that were provided will be
accessible in the global @_, the %ARGS hash, and any variables named in an
%args block.
For example, the below calls will all return '<b>Foo</b>':
execute('<b><% shift(@_) %></b>', 'Foo');
execute('<b><% $ARGS{label} %></b>', label=>'Foo');
execute('<%args>$label</%args><b><% $label %></b>', label=>'Foo');
Template Files¶
A parallel set of functions exist to handle templates which are stored in a
file:
$template = compile_file( './report_tmpl.msn' );
$result = $template->( %args );
$result = execute_file( './report_tmpl.msn', %args );
Template documents are just plain text files that contains the string to be
parsed. The files may have any name you wish, and the .msn extension shown
above is not required.
Error Checking¶
Both compilation and run-time errors in your template are handled as fatal
exceptions. The provided
try_execute() and
try_compile()
functions use a mixin class which wraps an eval { } block around the basic
execute() or
compile() methods. In a scalar context they return
the result of the call, or undef if it failed; in a list context they return
the results of the call (undef if it failed) followed by the error message
(undef if it succeeded). For example:
($result, $error) = try_execute( $mason_text );
if ( ! $error ) {
print $result;
} else {
print "Unable to execute template: $error";
}
A matching pair of try_*
_file() wrappers are available to catch run-time
errors in reading a file or parsing its contents:
($template, $error) = try_compile_file( './report_tmpl.msn' );
($result, $error) = try_execute_file( './report_tmpl.msn', %args );
For more information, see Text::MicroMason::CatchErrors.
Safe Compartments¶
If you wish to restrict the operations that a template can perform, use the
safe_compile() and
safe_execute() functions, or their try_*()
wrappers.
For more information, see Text::MicroMason::Safe.
SEE ALSO¶
For an overview of this templating framework, see Text::MicroMason.
For distribution, installation, support, copyright and license information, see
Text::MicroMason::Docs::ReadMe.