Hi,
I'm trying to convert a loop into a map construct.
I am trying to end up with a hash populated with only those name - value pairs that correspond to the values in an array.
I can do the loop, and am almost there with the map, but getting "use of unitialised value in hash assignment" and dont know why map is not dropping the value?
The loop at the top is what I've got, the map is almost what I want, thoughts? 
my %hash1 = ('one' => 'un', 'two' => 'deux', 'three' => 'trois');  # f
+ixed
my @ary   = ('one', 'two', 'four');                                # v
+ariable

#-----------------------------------------

for (keys %hash1) {
    my $loc = $_;
    my $mat = 0;
    for (@ary) {
        $mat = 1 if ($_ eq $loc);
    }
    delete $hash1{$loc} unless $mat;
}

for (keys %hash1) {
    print "**$_** => **$hash1{$_}**\n";
}

#-----------------------------------------

my %hash2 = map { $_ => $hash1{$_} if (defined $hash1{$_}) } @ary;

for (keys %hash2) {
    print "**$_** => **$hash2{$_}**\n";
}

#-----------------------------------------

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In reply to Mapping array over a hash by agoth

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