Is the exception specification part of the immediate context in SFINAE?

Question

This is a follow-up to the following question: SFINAE in variadic constructor

I wrote that some code such as

template<typename... Args>
StrongAlias(Args&&... args) noexcept(noexcept(T(std::declval<Args>()...)))
    : value(std::forward<Args>(args)...) {}

would disable the StrongAlias constructor in the case where T isn't constructible from the argument types, but another user told me that this wouldn't work because the exception specification isn't part of the immediate context.

Is the exception specification not part of the immediate context? I can't see why this would be the case.

https://timsong-cpp.github.io/cppwp/temp.deduct#7.note-1 – T.C. Mar 20 '18 at 20:06 — T.C., Mar 20 '18 at 20:06
@T.C. thanks, you should make that an answer – Brian Bi Mar 20 '18 at 20:07 — Brian Bi, Mar 20 '18 at 20:07

score 1 · Accepted Answer · answered Jun 23 '19 at 07:31

As pointed out by T.C. in comment, no. Per [temp.deduct]/7:

[ Note: The equivalent substitution in exception specifications is done only when the noexcept-specifier is instantiated, at which point a program is ill-formed if the substitution results in an invalid type or expression. — end note ]

Is the exception specification part of the immediate context in SFINAE?

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