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From: Jesse Jones (jesjones_at_[hidden])
Date: 2000-10-15 20:34:55

>>But what if the type is "char* const"? It won't match the specialization
>>because the pointer itself is const. I think there should be a second
>>specialization that looks like this:
>That was how it was in one of the early (pre-release) versions, but was
>changed to follow the definitions in 3.9.2 (compound types).

I'm sure you've already thrashed this out so I don't want to re-open a
long ago discussion, but I feel obligated to say this much:

1) I see nothing in sections 3.9.2 and 3.9.3 that make this sensible. The
closest I can find is the bit at the start of 3.9.3 that says that the
cv-qualified and cv-unqualified versions of a type are distinct types.
So, char* and char* const are distinct types, but they're still both

2) I expect that many people will be surprised to find that is_pointer
returns false for const pointers. So, it's important that this be well
documented (see below). It also wouldn't hurt to include a comment in the

>BTW the docs
>make it clear that is_pointer applies to cv-unqualified types,

Where? The type_traits.htm file merely says "True if T is a regular
pointer type - including function pointers - but excluding pointers to
member functions (3.9.2 p1 and 8.3.1)." This might be sort of clear if
"Regular pointers" were defined by the standard, but they're not. As far
as I'm concerned a char* const *is* a regular pointer.

  -- Jesse

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