My guess is that you managed to stave off the runtime-eval error by tricking perl with the qr// operator

Maybe. Although putting another eval string around it doesn't seem to change anything: 

$ perl -Mre=eval -e '/ (??{ eval "qr<(?{1})>" }) $_ /x'
$ perl -Mre=eval -e '/ (??{ eval "q<(?{1})>" }) $_ /x'
Eval-group not allowed ...

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perlre has an explicit distinction for interpolating qr// objects (under (?{}) instead). The problem is that I do use re "eval", but perl seems to forget. It does seems a little bug-ish, I'll perlbug it.

perlre: (?{ })
For reasons of security, this construct is forbidden if the regular expression involves run-time interpolation of variables, unless the perilous "use re 'eval'" pragma has been used (see re), or the variables contain results of "qr//" operator (see "qr/STRING/imosx" in perlop).

In reply to Re: Re: Spurious re 'eval'; warning ? by bsb
in thread Spurious re 'eval'; warning ? by bsb

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