Quoting from the Template::Manual::Directives perldoc page on the DEFAULT directive:-

The DEFAULT directive is similar to SET but only updates variables that are currently undefined or have no "true" value (in the Perl sense).

The following seems to work though:-

[% UNLESS n.defined && n.length; n = 1; END %]

In reply to Re: Template Toolkit, Default and Zero by dtr
in thread Template Toolkit, Default and Zero by marvell

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