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Message-ID:  <47df73f1-d26d-54ff-afab-b0237c6a933f@morningstar2.co.uk>
Date:         Fri, 21 Jul 2017 08:59:33 +0100
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From:         Joseph Wright <joseph.wright@MORNINGSTAR2.CO.UK>
Subject: \bool_if:n(TF) now *greedy*
To:           LATEX-L@LISTSERV.UNI-HEIDELBERG.DE
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Envelope-To: <rainer.schoepf@GMX.NET>
Status: R

Hello all,

The team have been working for some time to address an issue with
\bool_if:n(TF), namely that under some circumstances lazy evaluation can
lead to serious bugs. This is a consequence of working expandably and
cannot be avoided with lazy evaluation.

In the latest CTAN update, \bool_if:n(TF) has been made *greedy*:
\bool_lazy_... functions are available for lazy evaluation. (The latter
have a different input syntax which does not suffer from the issue that
affects \bool_if:n(TF).) Any code which still assumes lazy evaluation
for \bool_if:n(TF) will therefore need adjustment.

Regards,

Joseph