P0732R2 Class types in non-type template parameters #2171
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source/templates.tex
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| the type of the parameter is the type deduced | ||
| for the variable \tcode{x} in the invented declaration: | ||
| \begin{codeblock} | ||
| T x = @\grammarterm{template-argument}@ ; |
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Maybe try removing the italic corection after template-argument? There's more whitespace there than I'd prefer.
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That's a hard one. Fiddling with the italics correction doesn't change anything (same before and after):
\kern to the rescue:
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\itcorr[-1] does help:
That's:
T x = @\grammarterm{template-argument}@ ;
T x = @\grammarterm{template-argument}\itcorr[-1]@ ;
T x = @\grammarterm{template-argument}\kern-0.3em@ ;
I'm going with the \itcorr approach for consistency with what we do elsewhere. I think it also makes the left/right whitespace look more balanced than the 0.3em negative kerning hint.
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@zygoloid Does the \itcorr[-1] give you the same result as using \grammartermnc?
source/templates.tex
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| contains a placeholder type\iref{dcl.spec.auto} | ||
| or a placeholder for a deduced class type\iref{dcl.type.class.deduct}, | ||
| the type of the parameter is the type deduced | ||
| for the variable \tcode{x} in the invented declaration: |
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Consider removing the colon here.
source/templates.tex
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| @@ -1328,6 +1337,10 @@ | |||
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| const char p[] = "Vivisectionist"; | |||
| X<int,p> x2; // OK | |||
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| class A { constexpr A(const char*) {} }; | |||
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This example is wrong. Add a defaulted operator<=> here to fix it.
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The example is even more wrong: The type of the second template-parameter of X is still "const char *" and does not involve "A" at all.
source/templates.tex
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| X<A, "Pyrophoricity"> x3; // OK, string literal is a constructor argument to A | ||
| Y<"Pyrophoricity"> x3; // OK, string literal is a constructor argument to A |
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What's the rationale for the change from X to Y here?
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Never mind, I see it now. Looks like a change in P0732R2 was missing markup: I think we were supposed to change the rest of the example to:
template<class T, T p> class X {
/* ... */
};
X<const char*, "Studebaker"> x1; // error: string literal as template-argument
const char p[] = "Vivisectionist";
X<const char*,p> x2; // OK
The edits for decltype attributed to [dcl.type.class.deduct] were instead applied to [dcl.type.simple]. In [temp.param], the pointer-to-member case was struck, because it is subsumed by the more general bullet covering literal types. The first change attributed to [temp.type] was applied to [temp.arg.nontype] instead.
P0732R2 contained some changes to this section that were missing explicit markup; apply those changes too. Also fix missing definition of operator<=> in class type used as type of non-type template parameter.
zygoloid
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Fixes #2118.