next and anonymous blocks

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

The following next behavior was brought to my attention:

#!/usr/bin/perl
use strict;
use warnings;

foreach (1..5) {
    print "In for stmt\n";
    {
        next;
    }
    print "end of for stmt\n";
}
print "done.\n";
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In the above -- why does "end of stmt" get printed?

Alternatively, why isn't the following an error?

if (1) {
    print "In if stmt\n";
    { next; }
    print "end if for stmt\n";
}
print "done.\n";
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I would guess that the above implies that anonymous lexical scope is internally implemented as a foreach (1). Is that right? I am using perl 5.10.

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Re: next and anonymous blocks by kennethk (Abbot) on Mar 15, 2011 at 19:55 UTC
From next: Note that a block by itself is semantically identical to a loop that executes once. Thus next will exit such a block early. So your guess is essentially correct, though literal internal implementation is likely not that simple.	[reply]
Re: next and anonymous blocks by jwkrahn (Abbot) on Mar 15, 2011 at 20:43 UTC
the above implies that anonymous lexical scope is internally implemented as a `foreach (1).` `foreach` implies that `$_` is affected which is not the case here.	[reply] [d/l] [select]