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From: Steven Watanabe (watanabesj_at_[hidden])
Date: 2008-01-12 15:33:51


Joel de Guzman wrote:
> Valid Expressions:
> Expression Semantics
> ----------
> --------------------------------------------------------
> C::labels An MPL Sequence of Integral Constants

I think that a case should only have a single label. Allowing multiple
makes the implementation harder without adding any significant utility.
See below.

> case_<I>(f) Returns a Case object with supplied
> <snip more generators>

These can return fusion sequences of cases instead of plain cases.
This has the additional benefit that switch_ can be specified as taking
a fusion sequence of cases, without having to handle a single case

> default_(f) Returns a Case object with an empty labels list.
> forwarding to the encapsulated function object f.

 From the standpoint of the implementor of switch_, how do I figure out
Case is the default?

> * case_c and case_range_c are simple shortcuts. The type of
> integral constant is int. The actual type can be casted to
> the actual switch parameter. I think this is safe

Since the value is known at compile time the cast can be checked at
compile time to detect overflow.

In Christ,
Steven Watanabe

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