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Review:Needs Spec PR
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30a5e52 vs merge-base 10adc6c · about these metrics |
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…symbol slices __traits(vtblSymbol, T) is the vtbl of class T as a const(void*[]), and __traits(getInterfaces, T) is the Interface[] array of class or interface T as a const(Interface[]), i.e. the array the compiler places right after the ClassInfo. Like __traits(initSymbol, T) they are slices of symbols whose contents are only known at link time. CTFE now passes such slices through as opaque constants instead of erroring, so they can be stored (e.g. in a static initializer built at compile time), cast to another array type, and have their .length read; their contents still cannot be read.
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Oh, when did the spec get merged into DMD? What a luxury! |
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It's pretty terrible that CI takes over an hour... |
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Terrible, but unsurprising. |
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What is the application of alternative ClassInfo? Better C++ interop? |
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I'm writing alternative ClassInfo, so these traits make it possible to name the relevant symbols.
A following PR will make ClassInfo defined by the runtime rather than compiler magic.
__traits(vtblSymbol, T) is the vtbl of T as const(void*[]), and __traits(getInterfaces, T) is the Interface[] array of class or interface T as const(Interface[]), i.e. the array the compiler places right after the ClassInfo. Like __traits(initSymbol, T) they are slices of symbols whose contents are only known at link time.
CTFE now passes such slices through as opaque constants instead of erroring, so they can be stored (e.g. in a static initializer built at compile time), cast to another array type, and have their .length read; their contents can't be read.