Template::Plugin::Assert(3) User Contributed Perl Documentation Template::Plugin::Assert(3)

Template::Plugin::Assert - trap undefined values

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

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

Andy Wardley <abw@wardley.org> http://wardley.org/

Copyright (C) 2008-2022 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.

Template::Plugin

2023-07-25 perl v5.38.0