tmp/tmpwmvwes2y/{from.md → to.md}
RENAMED
|
@@ -0,0 +1,49 @@
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 1 |
+
#### Calling a function with a `tuple` of arguments <a id="tuple.apply">[[tuple.apply]]</a>
|
| 2 |
+
|
| 3 |
+
``` cpp
|
| 4 |
+
template <class F, class Tuple>
|
| 5 |
+
constexpr decltype(auto) apply(F&& f, Tuple&& t);
|
| 6 |
+
```
|
| 7 |
+
|
| 8 |
+
*Effects:* Given the exposition-only function:
|
| 9 |
+
|
| 10 |
+
``` cpp
|
| 11 |
+
template <class F, class Tuple, size_t... I>
|
| 12 |
+
constexpr decltype(auto)
|
| 13 |
+
apply_impl(F&& f, Tuple&& t, index_sequence<I...>) { // exposition only
|
| 14 |
+
return INVOKE(std::forward<F>(f), std::get<I>(std::forward<Tuple>(t))...);
|
| 15 |
+
}
|
| 16 |
+
```
|
| 17 |
+
|
| 18 |
+
Equivalent to:
|
| 19 |
+
|
| 20 |
+
``` cpp
|
| 21 |
+
return apply_impl(std::forward<F>(f), std::forward<Tuple>(t),
|
| 22 |
+
make_index_sequence<tuple_size_v<decay_t<Tuple>>>{});
|
| 23 |
+
```
|
| 24 |
+
|
| 25 |
+
``` cpp
|
| 26 |
+
template <class T, class Tuple>
|
| 27 |
+
constexpr T make_from_tuple(Tuple&& t);
|
| 28 |
+
```
|
| 29 |
+
|
| 30 |
+
*Effects:* Given the exposition-only function:
|
| 31 |
+
|
| 32 |
+
``` cpp
|
| 33 |
+
template <class T, class Tuple, size_t... I>
|
| 34 |
+
constexpr T make_from_tuple_impl(Tuple&& t, index_sequence<I...>) { // exposition only
|
| 35 |
+
return T(get<I>(std::forward<Tuple>(t))...);
|
| 36 |
+
}
|
| 37 |
+
```
|
| 38 |
+
|
| 39 |
+
Equivalent to:
|
| 40 |
+
|
| 41 |
+
``` cpp
|
| 42 |
+
return make_from_tuple_impl<T>(forward<Tuple>(t),
|
| 43 |
+
make_index_sequence<tuple_size_v<decay_t<Tuple>>>{});
|
| 44 |
+
```
|
| 45 |
+
|
| 46 |
+
[*Note 1*: The type of `T` must be supplied as an explicit template
|
| 47 |
+
parameter, as it cannot be deduced from the argument
|
| 48 |
+
list. — *end note*]
|
| 49 |
+
|