inner loop in switch

[Gil Shoam]

Hi,

I'm trying to do an inner loop using the switch option.
I want to do something like this:

switch(options){
case(a):
//do something
break;
case(b):
//do something
break;
case(c)
//do something
if(something)
//redo case(a)
if(somethingElse)
//redo case(b)
break;
}

I know I can just copy paste the code.. but is there a more elegant way to do it?

Thanks

[Jeff Verdegan]

Put the code in a method.

[Gil Shoam]

Jeff Verdegan wrote:Put the code in a method.

isn't there a "redo case(a)"
or something similar?

[Bear Bibeault]

No.

Methods are the accepted way to create reusable code, why do you need something different?

[Rob Spoor]

Do you need to redo case(a) twice if both conditions are true? If not you can reorder your case statements and use fall through:

switch(options){  
    // case(a) moved down
    case(b):  
        //do something  
        break;  
    case(c)  
        //do something  
        if(!something && !somethingElse)  
            break;  
        // else fall through
    case(a):  
        //do something  
        break;  
}  

I'd still prefer a separate method though.

[Campbell Ritchie]

Rob Spoor wrote: . . . I'd still prefer a separate method though.

Agree. Fall-through will confuse the next person who reads that code.

[Joanne Neal]

Rob - that code is wrong for when somethingElse is true - notice that OP wanted to redo case b in that situation.

[Campbell Ritchie]

Joanne Neal wrote:Rob - that code is wrong for when somethingElse is true - notice that OP wanted to redo case b in that situation.

so it confused the first person who read the code too?

Edit: change last to first

[Winston Gutkowski]

Campbell Ritchie wrote:

Rob Spoor wrote: . . . I'd still prefer a separate method though.

Agree. Fall-through will confuse the next person who reads that code.

Seconded. I think they could have saved us all a lot of bother (and break statements) by just making each section an independent block. After all, you can't use Duff's device, which is why a lot of us old C-ers liked the original syntax.

Winston

[Campbell Ritchie]

What’s Duff’s device? Is this it?

[Winston Gutkowski]

Campbell Ritchie wrote:What’s Duff’s device? Is this it?

Yup.

Winston

[Rob Spoor]

Joanne Neal wrote:Rob - that code is wrong for when somethingElse is true - notice that OP wanted to redo case b in that situation.

You're very right, I missed that. Another reason to use methods

[Winston Gutkowski]

Gil Shoam wrote:I know I can just copy paste the code.. but is there a more elegant way to do it?

I hesitate to suggest this, because you need to be careful and it is rather brittle; but you could use recursion, viz:

public void switchMethod(options) {
   switch(options){
      case(a):
         //do something
         break;
      case(b):
         //do something
         break;
      case(c)
         //do something
         if(something)
            switchMethod(case(a));
         if(somethingElse)
            switchMethod(case(b));
         break;
   }
}

Winston

[Randall Twede]

i guess i make it unanimous. method calls are the best way to go. i have written quite a few if-else and switch statements and put all the code in them. most of the time when i read them later i see i should have created a method or two and called them instead