comment on

Returning more (or less even) elements than provided is very natural for map and very commonly used, especially for generating hashes .. here's two relatively trivial examples:

perl -MData::Dumper -le 'my %cubes = map { $_ => $_**3 } 1..4; print D
+umper \%cubes'
$VAR1 = {
          '1' => '1',
          '2' => '8',
          '3' => '27',
          '4' => '64'
        };

my @users = [ {id=>4324, name=>'blah'}, {id=>1234, name=>'stuff'}, {id
+=>5678, name=>'foo'} ];
my %usersByName = map { $_->{id} => $_ } @users;
my $id = prompt_for_user_id;
my $user = $usersByName{$id};
[download]

Also, see map for more examples (including the basic hash creation), and this quote:

Evaluates BLOCK or EXPR in list context, so each element of LIST may produce zero, one, or more elements in the returned value.

In reply to Re: Parsing attributes in one line using map by davidrw
in thread Parsing attributes in one line using map by ruoso

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