Recently in a perl list someone ask how to clean an array, then i said @a=() or $#a=-1, but you can use undef @a too.
But i dont know what exatly do undef,heres and example to show what i mean:
perl -le 'use strict;my @a=("a");@a=();print "Defined" if defined @a;p
+rint scalar @a'

[download]
Defined
0
perl -le 'use strict;my @a=("a");undef @a;print "Defined" if defined @
+a;print scalar @a'

[download]
Defined
0
perl -le 'use strict;my @a=("a");@a=undef;print "Defined" if defined @
+a;print scalar @a'

[download]
Defined
1

Its still avaliable and strict dont warn it, then its not undefined, perhaps it is only memory deallocated, i dont know ...
I read that i shouldnt use undef on arrays on perldoc -f defined but i want to know what undef do :)
$anarion=\$anarion;

Edit Masem - CODE tags

s==q^QBY_^=,$_^=$[x7,print

In reply to using undef on a array by Anarion

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