Re: Re: Re: Getting data out of __DATA__ and __END_

I hope this doesn't come out wrong but...
Where are people getting this "$_ only happens in a regular while loop stuff? I would like to see a reference. I routinely use one liners like print while (<>). I think this might be confussion with the $_ magic assignment only happens in a while loop when using the <> operator. Can anyone correct me on this? BTW I <e>really</e> liked demerphq's

my @words = map { split " ",$_ } <DATA>;
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solution. Ugh, Zog say map gooood.

~~I also subscribe to the unsubstantiated opinion that a statement like~~

my @ary = split (" ", $_) while (<DATA>);
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is exactly like
while (<DATA>) { my @ary = split (" ", $_); }
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which would kinda explain this behavior.

again, I would love to be corrected on this and shown the errors of my ways.

I'm a sinner! Ira punnishes his wicked flesh bad, bad flesh. After running some code samples I have no answers but only questions.

So clearly the my declaration of array is *not* local to some implicit scope because use strict doesn't complain when you access it later in the file. And so I used the Dump procedure from Devel::Peek and the plot thickened...

use strict;
use warnings;
use Devel::Peek;

my @array = split (" ", $_) while (<DATA>);

print Dump(\@array);

__DATA__
ksg gae agdg ekau eg
Gke geo g ep ge
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Gave me...

SV = RV(0x1a97584) at 0x1a7f0bc
  REFCNT = 1
  FLAGS = (TEMP,ROK)
  RV = 0x1a72ffc
  SV = PVAV(0x1a7dd3c) at 0x1a72ffc
    REFCNT = 2
    FLAGS = (PADBUSY,PADMY)
    IV = 0
    NV = 0
    ARRAY = 0x1a7012c
    FILL = -1
    MAX = 4
    ARYLEN = 0x0
    FLAGS = (REAL)
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Note that MAX is 4? When I do this on an empty, never accessed array MAX is -1. So I think that somewhere along the way @array got 4 elements assigned to it. But that's also weird because there should have been 5.

Any hubris I had is now confussion. All is lost... all is lost...

Ira.

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No such thing as a small change
	PerlMonks

Re: Re: Re: Getting data out of __DATA__ and __END__

Re: Re: Re: Getting data out of DATA and END