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[basic.fundamental] Harmonize "Type X is a distinct type..." wordings #8762

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[basic.fundamental] Harmonize "Type X is a distinct type..." wordings #8762

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7 changes: 4 additions & 3 deletions source/basic.tex
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Original file line number Diff line number Diff line change
Expand Up @@ -5521,15 +5521,15 @@
\indextext{\idxcode{char8_t}|see{type, \tcode{char8_t}}}%
\indextext{type!\idxcode{char8_t}}%
\indextext{type!underlying!\idxcode{char8_t}}%
Type \keyword{char8_t} denotes a distinct type
Type \keyword{char8_t} is a distinct type
whose underlying type is \tcode{\keyword{unsigned} \keyword{char}}.
\indextext{\idxcode{char16_t}|see{type, \tcode{char16_t}}}%
\indextext{\idxcode{char32_t}|see{type, \tcode{char32_t}}}%
\indextext{type!\idxcode{char16_t}}%
\indextext{type!\idxcode{char32_t}}%
\indextext{type!underlying!\idxcode{char16_t}}%
\indextext{type!underlying!\idxcode{char32_t}}%
Types \keyword{char16_t} and \keyword{char32_t} denote distinct types
Types \keyword{char16_t} and \keyword{char32_t} are distinct types
whose underlying types are \tcode{std::uint_least16_t} and \tcode{std::uint_least32_t},
respectively, in \libheaderref{cstdint}.

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\end{note}

\pnum
The types denoted by \cv~\tcode{std::nullptr_t} are distinct types.
Type \tcode{std::nullptr_t} is a distinct type.
A prvalue of type \tcode{std::nullptr_t} is a null pointer
constant\iref{conv.ptr}. Such values participate in the pointer and the
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@Quuxplusone Quuxplusone Mar 2, 2026

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The sentence I'm modifying here was added by CWG2689 "Are cv-qualified std::nullptr_t fundamental types?" in 2024.

Incidentally, I wonder whether the previous emphasis on cv nullptr_t was supposed to imply something here: that maybe prvalues of type, say, volatile nullptr_t are not null pointer constants? Would that be detectable in any way?

I think it might be impossible to form a prvalue of type const nullptr_t or volatile nullptr_t, though. Certainly one can't do it via [conv.lval]: "A glvalue of a non-function, non-array type T can be converted to a prvalue. [...] If T is a non-class type, the type of the prvalue is the cv-unqualified version of T. [...] If T is cv std::nullptr_t, the result is a null pointer constant."

pointer-to-member conversions\iref{conv.ptr,conv.mem}.
\tcode{\keyword{sizeof}(std::nullptr_t)} shall be equal to \tcode{\keyword{sizeof}(\keyword{void}*)}.

\pnum
Type \tcode{std::meta::info} is a distinct type.
A value of type \tcode{std::meta::info} is called a \defn{reflection}.
There exists a unique \defnadj{null}{reflection};
every other reflection is a representation of
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