Re^4: Array ending up empty when processing more than a single file

I'm confused ... isn't this the old "won't stay shared" discussion?

Named subs are defined at compile time, that's why you can call a sub which is defined later.

A closure can only "share" the set of closed over variables it sees at definition time.

(i.e. name and reference are added to the "lexical pad" compare PadWalker)

That's why nesting named subs are discouraged in Perl.

edit

But when using an anonymous sub, the definition happens at run time.

something like

*name = sub {...} would solve this.

Cheers Rolf
_{(addicted to the Perl Programming Language and ☆☆☆☆ :)

Je suis Charlie!}

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Re^5: Array ending up empty when processing more than a single file by Your Mother (Archbishop) on Oct 05, 2017 at 18:01 UTC
You are completely correct. I was being dense. :P `>perl -wle 'for(1,2){ eval "sub moo{}" }; sub moo{};' Subroutine moo redefined at (eval 1) line 1. Subroutine moo redefined at (eval 2) line 1.` [download]	[reply] [d/l]
Re^5: Array ending up empty when processing more than a single file by Eily (Monsignor) on Oct 06, 2017 at 01:36 UTC
I guess that's actually the reverse discussion. There's just no "warning, the variable WILL stay shared" :-P	[reply]
Re^6: Array ending up empty when processing more than a single file by LanX (Saint) on Oct 06, 2017 at 01:57 UTC
As I said: I'm confused... > There's just no "warning, the variable WILL stay shared" :-P There might be no warning, but it's still the same problem. You proved that from the second run on `$var` isn't shared anymore. Just a minor change to your code, and the warning appears: `use strict; use warnings; $\ = $/; tst() for (1..2); sub tst { my $var = 1; print \$var, " created"; sub func { print \$var; } func(); }` [download] `Variable "$var" will not stay shared at d:/pm/wont_stay_shared.pl line + 13. SCALAR(0x4c97f0) created SCALAR(0x4c97f0) SCALAR(0x4a8420) created SCALAR(0x4c97f0)` [download] Looks like you found a case insufficiently covered by warnings! Cheers Rolf _{(addicted to the Perl Programming Language and ☆☆☆☆ :) Je suis Charlie!}	[reply] [d/l] [select]
Re^7: Array ending up empty when processing more than a single file by Eily (Monsignor) on Oct 06, 2017 at 08:10 UTC
Oh right, I just glanced over the Variable will not stay shared in a sporadically crashing CGI thread so I mostly guessed what it was about rather than knew. After actually reading it, I see you're definitely right.	[reply]
Re^8: Array ending up empty when processing more than a single file by LanX (Saint) on Oct 06, 2017 at 08:59 UTC