Re: Why can't switch be used for objects

Bruce Wood <brucewood@xxxxxxxxxx> wrote:
> 1. Because it would be grossly slow.
> 2. Because the semantics of comparison are unclear (do you use equality
> by reference, or use the Equals method, or do you allow IComparers,
> or... ?)
> 3. Because if you need this then there is probably some other (cleaner)
> way to do what you want to do... which is why I'm wondering exactly
> where you need this switch statement and for what, in order to propose
> an alternate design. :-)

Actually, it's not entirely unreasonable, nor does it need to be slow -
with some extra support.

I've recently been playing around with Java 1.5's enums, which allow
switching and all kinds of fun. They're much more powerful than the
..NET enums - although there are certain bits of behaviour from .NET's
"simple" enums which Java makes slightly harder.

--
Jon Skeet - <skeet@xxxxxxxxx>
http://www.pobox.com/~skeet
If replying to the group, please do not mail me too
.

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