From Jason Turner

[meta.define.static]

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tmp/tmp4y6spm8k/{from.md → to.md} RENAMED
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+ ### Promoting to static storage <a id="meta.define.static">[[meta.define.static]]</a>
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+
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+ The functions in this subclause promote compile-time storage into static
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+ storage.
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+
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+ ``` cpp
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+ template<ranges::input_range R>
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+ consteval info reflect_constant_string(R&& r);
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+ ```
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+
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+ Let `CharT` be `ranges::range_value_t<R>`.
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+
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+ *Mandates:* `CharT` is one of `char`, `wchar_t`, `char8_t`, `char16_t`,
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+ `char32_t`.
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+
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+ Let V be the pack of values of type `CharT` whose elements are the
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+ corresponding elements of `r`, except that if `r` refers to a string
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+ literal object, then V does not include the trailing null terminator of
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+ `r`.
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+
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+ Let P be the template parameter object [[temp.param]] of type
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+ `const CharT[sizeof...(V) + 1]` initialized with `{`V`..., CharT()}`.
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+
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+ *Returns:* .
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+
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+ [*Note 1*: P is a potentially non-unique
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+ object [[intro.object]]. — *end note*]
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+
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+ ``` cpp
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+ template<ranges::input_range R>
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+ consteval info reflect_constant_array(R&& r);
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+ ```
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+
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+ Let `T` be `ranges::range_value_t<R>`.
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+
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+ *Mandates:* `T` is a structural type [[temp.param]],
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+ `is_constructible_v<T, ranges::range_reference_t<R>>` is `true`, and
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+ `is_copy_constructible_v<T>` is `true`.
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+
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+ Let V be the pack of values of type `info` of the same size as `r`,
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+ where the iᵗʰ element is `reflect_constant(``eᵢ``)`, where `eᵢ` is the
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+ iᵗʰ element of `r`.
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+
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+ Let P be
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+
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+ - If `sizeof...(`V`) > 0` is `true`, then the template parameter
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+ object [[temp.param]] of type `const T[sizeof...(`V`)]` initialized
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+ with `{[:`V`:]...}`.
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+ - Otherwise, the template parameter object of type `const array<T, 0>`
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+ initialized with `{}`.
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+
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+ *Returns:* .
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+
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+ *Throws:* `meta::exception` unless `reflect_constant(e)` is a constant
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+ subexpression for every element `e` of `r`.
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+
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+ [*Note 2*: P is a potentially non-unique
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+ object [[intro.object]]. — *end note*]
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+
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+ ``` cpp
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+ template<ranges::input_range R>
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+ consteval const ranges::range_value_t<R>* define_static_string(R&& r);
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+ ```
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+
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+ *Effects:* Equivalent to:
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+
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+ ``` cpp
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+ return meta::extract<const ranges::range_value_t<R>*>(meta::reflect_constant_string(r));
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+ ```
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+
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+ ``` cpp
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+ template<ranges::input_range R>
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+ consteval span<const ranges::range_value_t<R>> define_static_array(R&& r);
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+ ```
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+
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+ *Effects:* Equivalent to:
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+
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+ ``` cpp
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+ using T = ranges::range_value_t<R>;
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+ meta::info array = meta::reflect_constant_array(r);
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+ if (meta::is_array_type(meta::type_of(array))) {
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+ return span<const T>(meta::extract<const T*>(array), meta::extent(meta::type_of(array)));
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+ } else {
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+ return span<const T>();
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+ }
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+ ```
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+
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+ ``` cpp
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+ template<class T>
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+ consteval const remove_cvref_t<T>* define_static_object(T&& t);
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+ ```
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+
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+ *Effects:* Equivalent to:
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+
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+ ``` cpp
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+ using U = remove_cvref_t<T>;
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+ if constexpr (meta::is_class_type(^^U)) {
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+ return addressof(meta::extract<const U&>(meta::reflect_constant(std::forward<T>(t))));
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+ } else {
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+ return define_static_array(span(addressof(t), 1)).data();
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+ }
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+ ```
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+
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+ [*Note 3*: For class types, `define_static_object` provides the address
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+ of the template parameter object [[temp.param]] that is
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+ template-argument equivalent to `t`. — *end note*]
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+