my $total_to_two_decimal_places = sprintf("%.2f", $price);

sub dollar_str_subroutine {
# --------------------------------------------------
# create the dollar string creation function
# takes advantage of closures to speed up the operation
#

my $currency_pre_symbol = '';
my $currency_post_symbol = '$';
my $currency_group_separator = ',';
my $currency_digits_ingroup = 3;
my $currency_decimal_point = '.';
my $currency_decimal_places = '2';

my $dollar_str_sub = sub {
my $dollar_amount = shift || 0;
my $dollar_str = sprintf( "%.0".$currency_decimal_places."f", $dollar_amount );

if ( $currency_group_separator ) {
my $i = index( $dollar_str, '.' ) || '';
my $cents = substr( $dollar_str, $i+1 ) || '';
my $dollars = reverse substr( $dollar_str, 0, $i );
$dollars =~ s,(\d{$currency_digits_ingroup}),$1$currency_group_separator,go;
$dollars =~ s,\Q$currency_group_separator\E$,,o;
$dollar_str = reverse( $dollars ) . $currency_decimal_point . $cents;
}
return $currency_pre_symbol . $dollar_str . $currency_post_symbol;
};

return $dollar_str_sub;
}

# EXAMPLE:
my $dsub = dollar_str_subroutine();
print $dsub->( 25.50 );