Is the behaviour of join with a tied scalar prior to 5.18.2 correct but not clearly explained in the documentation or is it a bug that has now been fixed?

Looks like it was a bug that finally got fixed ... probably as they were fixing an adjacent bug ... an optimization :)

Yup, a bug fixed by accident :) Fold join to const or stringify where possible
you'll see a TIESCALAR test but not as the first argument like you have :) http://perl5.git.perl.org/perl.git/blob/HEAD:/t/op/join.t
http://perl5.git.perl.org/perl.git/history/HEAD:/t/op/join.t

So you should perlbug this johngg to make it official

In reply to Re: Undocumented join() feature, now defunct? (bug) by Anonymous Monk
in thread Undocumented join() feature, now defunct? by johngg

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