[grep] searches arrays or lists.

I don't think so. Do you have any reason to believe grep knows anything about arrays? 

>perl -le"@a = qw( a b c d ); @b = grep { push(@a,'!') if !$i++; 1 } @
+a; print @b"
abcd

[download]

Contrast with for which does: 

>perl -le"@a = qw( a b c d ); for (@a) { push(@a,'!') if !$i++; push @
+b, $_ } print @b"
abcd!

[download]

In reply to Re^2: (Mis)Understanding <c>grep...eq $_<c> by ikegami
in thread (Mis)Understanding grep...eq $_ by ww

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