Name: wl91122 Date: 09/08/99


It would be nice if case labels allowed several comma separated values.

switch( i )
{
   case 1,3,5,7: foo();
}

would be equivalent to the less readable version

switch( i )
{
   case 1:
   case 3:
   case 5:
   case 7: foo();
}

In addition why not allow ranges as well? The two together allow you to
efficiently code things like:

switch( c )
{
    case 'A'-'Z','a'-'z':
        System.out.println( "letter" ); break;
    case '0'-'9':
        System.out.println( "number" ); break;
    default:
        System.out.println( "other" ); break;
}

As it stands now the only way to code this is using if statements but they
aren't as readable as this switch statement. You can tell at a glance what
this switch statement does. Compare that with:

if( c >= 'A' && c <='Z' || c >= 'a' && c <='z' )
    System.out.println( "letter" ); break;
else if( c >= '0' && c <= '9' )
    System.out.println( "number" ); break;
else
    System.out.println( "other" ); break;

I don't see any real problem with adding it to the language. Source code
that uses this construct would not be backwards compatible, but neither is
any code that uses a new API. The generated bytecode would still be
backwards compatible.

I really wish you could get rid of the fall-through behavior for switch statements,
but I understand that it's too late now and it must be kept that way for backwards
compatibility.
(Review ID: 95013)
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