Type traits revision proposal.

From: John Maddock (John_Maddock_at_[hidden])
Date: 2000-10-28 06:27:16

All,

It's apparent that I lost the argument in the recent type-traits
discussion, the following short list is a proposal for revising the type
traits library in line with the comments received, and at the same time
reorganising the library to make it easier to maintain and locate all the
implementations for a particular template.

1) All the templates will be insensitive to cv-qualifiers, except for those
like has_trivial_xxxx, which *must* take cv-qualifiers into account.

2) define a core set of templates, which for any given type, exactly one
will evaluate to true. Howard suggested:

is_integral
is_floating
is_void
is_pointer
is_reference
is_member_pointer
is_array
is_enum
is_union
is_class

Which looks to be a good start, some sub-categories (like
is_signed_integer) will remain however, as will some derived categories
(is_arithmetic etc).

3) depreciate the is_standard_xxx and is_extension_xxx templates - really
just to simplify the library - is anyone using these?

Any objections?  Anything I've missed?

- John.