[boost] Re: Proposal: strings as template parameters?

From: James Curran (jamescurran_at_[hidden])
Date: 2003-03-04 13:10:46

Jason House wrote:
>   Well, I know that in MSVC simply refuses to use strings as template
> parameters...  If this truly is illegal by the standard, then a string
> template parameter could default to a type for that string.  As far as
> use in other places, maybe use of some keyword as a function.  Like
> maybe struct("foo").

    Both the Standard & MSVC6 allow a (const char*) as a template parameter.
What is rejected (by both) is a text literal parameter.   For a non-type
parameter, the value must be a constant across all translation units linked
together, hence it must be defined extern.

    template <const char* S>   SomeClass { ...};

    SomeClass<"YourParam">   NoGood;

extern const char* MyParam = "MyParam";
    SomeClass<MyParam>    Acceptable;

--
Truth,
James Curran
www.noveltheory.com (personal)
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