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hi, i am pretty new to perl but this one really confuses me...i have taken some code and tried to make it as minimal as possible for the problem i'm getting

consider 'blah.pl'

#!/usr/bin/perl use strict; sub screwed { my ($in) = @_; open(IN, "<$in"); while(<IN>) { print "file $in contains $_"; } close(IN); } my @instances = ("a", "b"); map { print "before $_\n" } @instances; map { screwed "$_"; } @instances; map { print "after $_\n" } @instances;
and data file 'a'
a1 a2
and data file 'b'
b1 b2
running this i get
before a before b file a contains a1 file a contains a2 file b contains b1 file b contains b2 after after
what has happened to the entries of instances? they are there but are empty (null?)

if i remove the while (<IN>) line i get what i expect...

before a before b opening file named a opening file named b after a after b
so why does iterating over the <IN> with a while kill my instances list?!! i don't get it...

was getting this with a suse7 locally built perl5.6 and thinking it was (maybe) a perl bug i rebuily perl5.8.0 locally and am still getting it.. :( mat


In reply to opening a file destroys nulling entries in a list?!?! by matpalm

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