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Re: Urgent subroutine signatures problems

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From:
Father Chrysostomos
Date:
December 13, 2017 16:53
Subject:
Re: Urgent subroutine signatures problems
Message ID:
20171213165349.19184.qmail@lists-nntp.develooper.com
Paul Evans wrote:
> I haven't been keeping much eye on that part of the problem lately, but
> as a quick thought: how easy is it to skip over the signature at a very
> surface character-skipping level, find the attributes afterwards, apply
> them, and then come back to properly parsing the signature? Is it as
> easy as just counting the open and close parens, etc.?

No.  Unlike prototypes, signatures are properly parsed, allowing
things like ($a=")"), and even ($a=do{ BEGIN { ... } }), which pretty
much rules out any two-pass parsing.

(And please let's not extend the mistake of scanning for the clos-
ing delimiter first.  Perl's s/// parsing is buggy and unfixable as
a result.)

>   use 5.028;
>   no feature 'signatures';

It was my assumption that it would be added to the next feature bundle
when it lost its experimental status.  I think we should stick to that.

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