Sorry, merlyn, but the second example *is* turning a list into another list. map is very capable of mapping 1-to-n relations, ie, every element on the right will produce more than one element on the right.

If I read your statement correctly ( and I may not have ), the first use of map isn't correct 

my @first = qw/ one-1 two-2 three-3/;
my %hash  = map { split /-/ } @first; # Which works for me btw
print map { "$_ => $hash{$_}\n" } keys %hash;

[download]
But this usage is correct 
my @first = qw/ one-1 two-2 three-3/;
my @second  = map { split /-/ } @first;
my %hash = @second;  # Legal code, isn't it?
print map { "$_ => $hash{$_}\n" } keys %hash;

[download]

How else is map supposed to make @first into @second except by performing an action on every element of @first?

I am not arguing that a foreach wouldn't be appropriate here. If that is what works, by all means use it. But if I am not supposed to use map when I want an action on every element of an array, doesn't it make more sense to say 

@second = @first;

[download]
because that seems to be the only option you have left me with this statement.

Would you be kind enough to expand on your answer so I can figure out what I missed?

TIA
mikfire

In reply to Re: Re: Back to Remedial Perl for Me: map{} function by mikfire
in thread Back to Remedial Perl for Me: map{} function by jreades

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