Actually...here's full piece of code I need to enter:
if ( $phone =~ / ^ \( \d{3} \) \d{3} - \d{4} $ /x ) {
else {
print( div( { style => "color: red; font-size: x-large" },
"INVALID PHONE NUMBER" ), br() );
print( "A valid phone number must be in the form " );
print(...