use Data::Dumper;

sub get_day_name { "hlaghlag"; }

print Dumper { map { $_ => get_day_name($_) } <DATA> };

__END__
foo
bar
baz
[download]

Care to be more specific about "doesn't compile"?

I cannot reproduce your problem in 5.6.1. What doesn't compile about that latter statement? It looks fine logically and works fine on my system (taking liberty with the nature of your function and the data):

#!/usr/bin/perl

use Data::Dumper;

sub get_day_name {
        return "first"  if $_[0] =~ /one/;
        return "second" if $_[0] =~ /two/;
        return "third"  if $_[0] =~ /three/;
        return;
}

print Dumper {map {$_ => get_day_name($_)} <DATA>};

__DATA__
one
two
three
[download]

$VAR1 = {
          'two
' => 'second',
          'three
' => 'third',
          'one
' => 'first'
        };
[download]

You probably want a chomp in your map though to get rid of those newlines.

print Dumper [map {$_ => get_day_name($_)} <DATA>];
[download]

Update I should have read the question more closely. He does want a hash back. See clintp's response.

map's returning a list all right: in this case a list of paired elements. It's perfectly acceptable to dump this "list" directly into a hash.

It seems to work fine for me based on the current information. Are you sure you've actually got <DATA>? Did you already read it all in perhaps, leaving it with no more to read?

hmmm,

- danboo

Instead of using Perl's // to create a comment I was using /* */ to create a comment, which is gibberish to perl.

For the record '#' is used for creating comments in perl. Hopefully you figured that out already.

- danboo