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

by IraTarball (Monk)
on Sep 10, 2001 at 21:05 UTC ( #111510=note: print w/replies, xml ) Need Help??

in reply to Re: Re: Getting data out of __DATA__ and __END__
in thread 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>;
solution. Ugh, Zog say map gooood.

I also subscribe to the unsubstantiated opinion that a statement like

my @ary = split (" ", $_) while (<DATA>);
is exactly like
while (<DATA>) { my @ary = split (" ", $_); }
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
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)
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...


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