There was a detailed thread on this before. I don't have time to search for it right now, but it was determined that

%hash = map { getkey($_) => $_ } @array;

[download]

is closer to

@anon_temp = ();
foreach (@array) {
   push(@anon_temp, getkey($_), $_);
}
%hash = @anon_temp;

[download]

than to

%hash = ();
foreach (@array) {
   $hash{getkey($_)} = $_;
}

[download]

and that the %hash = @anon_temp; accounts for the speed difference.

As for your other question, my $something = $value if $something is similar to (or the same as?) (my $something = $value) if $something. The my in executes only if $something was true before this statement. Never use if, unless, etc on a my.

In reply to Re: Map: Thou Has't Confounded Me For The Last Time! (Referring To The Array You Are Assigning To In Map) by ikegami
in thread Map: Thou Has't Confounded Me For The Last Time! (Referring To The Array You Are Assigning To In Map) by Revelation

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