switch case failure

[JimS]

Re: switch case failure

On Tue, 11 Oct 2005 15:21:58 -0400, "Steve Fábián"
<ESFabian@BellA tlantic.net> wrote:
[color=blue][color=green][color=darkred]
>>>> switch (n)
>>>> {
>>>> case 1..3:
>>>> // do thing A
>>>> break;
>>>> case 4:
>>>> // do thing B
>>>> break;
>>>> default:
>>>> // do thing C
>>>> }
>>> I would tend to agree. My guess would be that they didn't want to change
>>> the same construct too much from the original C version. But that's just
>>> a guess, you'd have to ask the committee.
>>>[/color]
>> My guess is that for this minimum comfort we get a can of worms in the
>> parser design. . .[/color]
>
>It is a "minimum comfort" if the range is 1..3, but not if it is 1005..11004
>(you'd not like to list them as individual cases,would you). Yes, I know you
>can do it with an "if" instead, but if/elseif/elseif/elseif... is far less
>clear to the person validating the code.
>
>Personally, I'd like to see the "select first/select all" I mentioned before
>(with the ranges).[/color]

The problem is that you can't use 1..3 or 1...3 because then the way C
parsers work it will look like 1. which is a floating point number.
In GCC's case-range extension it has to look like 1 ... 3

You can always use a combination of switch/if/else, or if it all gets
a bit too hairy, use a jump table.

JimS