From Jason Turner

[range.elements.overview]

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  #### Overview <a id="range.elements.overview">[[range.elements.overview]]</a>
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- `elements_view` takes a `view` of tuple-like values and a `size_t`, and
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- produces a `view` with a value-type of the Nᵗʰ element of the adapted
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- `view`’s value-type.
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  The name `views::elements<N>` denotes a range adaptor object
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  [[range.adaptor.object]]. Given a subexpression `E` and constant
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  expression `N`, the expression `views::elements<N>(E)` is
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  expression-equivalent to
@@ -12,11 +12,11 @@ expression-equivalent to
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  [*Example 1*:
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  ``` cpp
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  auto historical_figures = map{
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- {"Lovelace"sv, 1815},
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  {"Turing"sv, 1912},
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  {"Babbage"sv, 1791},
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  {"Hamilton"sv, 1936}
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  };
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@@ -31,31 +31,31 @@ for (auto&& born : birth_years) {
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  }
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  ```
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  — *end example*]
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- `keys_view` is an alias for `elements_view<views::all_t<R>, 0>`, and is
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- useful for extracting keys from associative containers.
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  [*Example 2*:
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  ``` cpp
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- auto names = keys_view{historical_figures};
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  for (auto&& name : names) {
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  cout << name << ' '; // prints Babbage Hamilton Lovelace Turing
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  }
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  ```
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  — *end example*]
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- `values_view` is an alias for `elements_view<views::all_t<R>, 1>`, and
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- is useful for extracting values from associative containers.
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  [*Example 3*:
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  ``` cpp
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  auto is_even = [](const auto x) { return x % 2 == 0; };
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- cout << ranges::count_if(values_view{historical_figures}, is_even); // prints 2
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  ```
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  — *end example*]
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  #### Overview <a id="range.elements.overview">[[range.elements.overview]]</a>
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+ `elements_view` takes a view of tuple-like values and a `size_t`, and
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+ produces a view with a value-type of the Nᵗʰ element of the adapted
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+ view’s value-type.
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  The name `views::elements<N>` denotes a range adaptor object
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  [[range.adaptor.object]]. Given a subexpression `E` and constant
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  expression `N`, the expression `views::elements<N>(E)` is
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  expression-equivalent to
 
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  [*Example 1*:
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  ``` cpp
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  auto historical_figures = map{
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+ pair{"Lovelace"sv, 1815},
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  {"Turing"sv, 1912},
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  {"Babbage"sv, 1791},
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  {"Hamilton"sv, 1936}
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  };
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  }
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  ```
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  — *end example*]
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+ `keys_view` is an alias for `elements_view<R, 0>`, and is useful for
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+ extracting keys from associative containers.
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  [*Example 2*:
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  ``` cpp
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+ auto names = historical_figures | views::keys;
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  for (auto&& name : names) {
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  cout << name << ' '; // prints Babbage Hamilton Lovelace Turing
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  }
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  ```
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  — *end example*]
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+ `values_view` is an alias for `elements_view<R, 1>`, and is useful for
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+ extracting values from associative containers.
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  [*Example 3*:
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  ``` cpp
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  auto is_even = [](const auto x) { return x % 2 == 0; };
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+ cout << ranges::count_if(historical_figures | views::values, is_even); // prints 2
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  ```
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  — *end example*]
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