The thing as, as I understand the documentation of perlre, [use strict; our $x = qr/... (??{ $x }) .../ ] should be allowed

You're using a variable ($x) you haven't declared yet. It's a strict error just like 

$ perl -e'use strict; our $x = $x;'

$

[download]

huh... what? I guess I was wrong. our declarations take effect immediately. I don't see why «our $x = $x;» and «our $x = qr/(??{ $x })/;» can behave differently. It would seem there's a bug here.

In reply to Re^5: (??{ code }) versus (?PARNO) for recursive regular expressions by ikegami
in thread (??{ code }) versus (?PARNO) for recursive regular expressions by wind

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