[cstdlib.syn, csignal.syn] Introduce exposition-only function types with C and C++ language linkage to improve the presentation of C library functions that take callbacks. #1049
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| @@ -3039,12 +3039,18 @@ | |||
| #define MB_CUR_MAX @\seebelow@ | |||
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| namespace std { | |||
| // Exposion-only function type aliases | |||
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| #define MB_CUR_MAX @\seebelow@ | |||
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| namespace std { | |||
| // Exposition-only function type aliases | |||
| extern "C" using c_exit_t = void(); // \expos | |||
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[objects.within.classes]/2 only defines what the "// exposition only" comment means for private members of classes. This isn't the only place where we would be using it for something else, but it might be a good idea to move the definition of "exposition only" to somewhere more general, and just refer to it from [objects.within.classes]/2.
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Added a new subclause to define exposition-only types.
| @@ -3039,12 +3039,18 @@ | |||
| #define MB_CUR_MAX @\seebelow@ | |||
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| namespace std { | |||
| // Exposition-only function type aliases | |||
| extern "C" using c_exit_t = void(); // \expos | |||
| extern "C++" using cxx_exit_t = void(); // \expos | |||
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This is the only use of "cxx" to refer to C++ in the standard; we use "cpp" in the few places where this comes up. Perhaps we could just omit the cxx_ prefix and maybe also the extern "C++"?
I would also avoid an _t name, since that makes it look more like this is a name exposed by the library. Maybe even avoiding a real identifier entirely, and/or using an alternative typographical convention, would help to emphasize that this is not an exposed name:
usingatexit-handler= void(); //exposition only
extern "C" usingc-atexit-handler= void(); //exposition only
int atexit(atexit-handler* func);
int atexit(c-atexit-handler* func);
int at_quick_exit(atexit-handler* func);
int at_quick_exit(c-atexit-handler* func);
... although I note that none of our existing exposition-only names use such a typographical convention.
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I removed cxx_ and renamed the typedefs to _fn.
I like the placeholder style, but take note that we we will need to refer to that name in the itemdescls as well, which are quite far way (see updated PR).
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I retained the extern "C++", because it makes the columns line up nicely :-S
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I implemented the placeholder types.
| extern "C" int at_quick_exit(void (*func)()); | ||
| extern "C++" int at_quick_exit(void (*func)()); | ||
| int atexit(c_exit_t* fuc); | ||
| int atexit(cxx_exit_t* fuc); |
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Looks like you accidentally lost an 'n' here.
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…ith C and C++ language linkage to improve the presentation of C library functions that take callbacks. This change improves correctness, since we never meant to specify the language linkage of the function names, but only of the callback parameter type. Fixes cplusplus#1002.
This change improves correctness, since we never meant to specify the language linkage of the function names, but only of the callback parameter type.
Fixes #1002.