Confusion with context

[thinker]

Hello everyone

I was writing a function to extract enum values from a mysql table, when I encountered something which confused me. My first attempt was

sub get_enums {

        my ($field, $table) = @_;

        my $dbh = get_ka_dbh();
        my $sql = qq/SHOW COLUMNS FROM $table LIKE "$field"/;

        my $sth = $dbh->prepare($sql) or die $!;

        $sth->execute();

        my $ref = $sth->fetchrow_arrayref();
        my ($f) = $ref -> [1] =~ /enum\('(.*)'\)/ ;
        return split "','", $f;
}

This works fine, but I felt there should be no need for the temporary $f variable

My first attempts at removing it brought failure, as the $ref -> [1] =~ /enum\('(.*)'\)/ was returning in the wrong context (I think), and returning "1".

After some experimentation I discovered that what I wanted could be achieved by  return split  "','",   ( $ref->[1] =~ /enum\('(.*)'\)/ )[0];

I have decided that my original version, with temp variable, is clearest, and will be what i use, but I wonder if anyone could kindly explain what is happening here, and why I need the [0] at the end

Thank You

thinker