Re: [exim] def:acl var with strict_acl_vars=true

Kjetil Torgrim Homme wrote:

> this is a bit inaccurate. def on a variable whose contents is "0" will
> still return a truth value.

True. The meaning of def: is not "is it defined?", but more like "is
there something in in?". So "def:var" is short for "!eq{$var}{}".

> I don't see the harm in making the change Brian asks for -- it will

It's a change of behaviour. strict_acl_vars was introduced to protect
against typos, like Perl's "use strict". If there is a use case for such
a check, it should be done with a new expansion condition, e.g. "isset:var".