共通祖先

• 2014-01-17, N3851 Multidimensional bounds, index and array_view : array_view
  • N3976(r2), N4087(r3), N4177(r4), N4346(r5), N4494(r6)
• 2015-05-07, N4512 Multidimensional bounds, offset and array_view, revision 7 : array_view

std::span (C++20)

• 2015-09-25, P0122R0 array_view: bounds-safe views for sequences of objects : array_view
  • "The design of the array_view type discussed in this paper is related to the array_view previously proposed in N3851 and also drew on ideas in the array_ref and string_ref classes proposed in N3334."
• 2016-02-11, P0122R1 span: bounds-safe views for sequences of objects : span
  • "Changed the name of the type being proposed from array_view to span following feedback from LEWG at the Kona meeting."
  • "Removed multidimensional aspects from the proposal. span is now always single-dimension and contiguous."
• 2018-03-16, P0122R7 span: bounds-safe views for sequences of objects : span (Adopted 2018-03)

std::mdspan (C++23)

• 2015-09-23, P0009R0 Polymorphic Multidimensional Array View : view
  • "Thus we choose the name view as opposed to array_view in anticipation of this new fundamental mechanis for viewing spans of memory with an easily extensible set of properties."
• 2016-02-04, P0009R1 Polymorphic Multidimensional Array Reference : array_ref
  • "Revised with renaming from view to array_ref and allow unbounded rank through variadic arguments." (quote from P0009R2)
• 2016-10-14, P0009R3 Polymorphic Multidimensional Array Reference : array_ref
  • "Note that the array_ref name in this paper is not entirely satisfactory and the following alternatives were brainstormed during prior LEWG reviews."
  • "LEWG 2015-10-22: view, span, array_ref, slice, array_view, ref, array_span, basic_span, object_span, field"
  • "LEWG 2016-06-25: sci_span, numeric_span, multidimensional_span, multidim_span, md_span, vla_span, multispan, multi_span"
• 2017-10-11, P0009R4 Polymorphic Multidimensional Array Reference : mdspan
  • "Rename to mdspan, multidimensional span, to align with P0122r5 span."
• 2022-07-13, P0009R18 MDSPAN : mdspan (Adopted 2022-07)

https://cpplover.blogspot.com/2017/10/c-p0009r4-p0237r9.html

もともとarray_viewだったが、今ではmdspanという一見してわけのわからない名前になっている。これは、viewという用語が適切ではないという意見によって変更された。

https://cpplover.blogspot.com/2017/10/c-p0260r2-p0356r2.html

しかし、連続したストレージを所有しない多次元配列に見せかけるラッパークラスとして、mdspanという名前は本当に通じるのだろうか。これはもともとarray_viewと呼ばれていたが、viewという用語は正しくないと物言いがついたために、spanになった。