phpman > perldoc > Template::Plugin::Assert(3pm)

NAME
    Template::Plugin::Assert - trap undefined values

SYNOPSIS
        [% USE assert %]

        # throws error if any undefined values are returned
        [% object.assert.method %]
        [% hash.assert.key %]
        [% list.assert.item %]

DESCRIPTION
    This plugin defines the "assert" virtual method that can be used to automatically throw errors
    when undefined values are used.

    For example, consider this dotop:

        [% user.name %]

    If "user.name" is an undefined value then TT will silently ignore the fact and print nothing. If
    you "USE" the "assert" plugin then you can add the "assert" vmethod between the "user" and
    "name" elements, like so:

        [% user.assert.name %]

    Now, if "user.name" is an undefined value, an exception will be thrown:

        assert error - undefined value for name

AUTHOR
    Andy Wardley <abw AT wardley.org> <http://wardley.org/>

COPYRIGHT
    Copyright (C) 2008 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.

SEE ALSO
    Template::Plugin