xref: /freebsd/contrib/llvm-project/libc/src/__support/CPP/array.h (revision bb722a7d0f1642bff6487f943ad0427799a6e5bf)
1*bb722a7dSDimitry Andric //===-- A self contained equivalent of std::array ---------------*- C++ -*-===//
2*bb722a7dSDimitry Andric //
3*bb722a7dSDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4*bb722a7dSDimitry Andric // See https://llvm.org/LICENSE.txt for license information.
5*bb722a7dSDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6*bb722a7dSDimitry Andric //
7*bb722a7dSDimitry Andric //===----------------------------------------------------------------------===//
8*bb722a7dSDimitry Andric 
9*bb722a7dSDimitry Andric #ifndef LLVM_LIBC_SRC___SUPPORT_CPP_ARRAY_H
10*bb722a7dSDimitry Andric #define LLVM_LIBC_SRC___SUPPORT_CPP_ARRAY_H
11*bb722a7dSDimitry Andric 
12*bb722a7dSDimitry Andric #include "src/__support/CPP/iterator.h" // reverse_iterator
13*bb722a7dSDimitry Andric #include "src/__support/macros/attributes.h"
14*bb722a7dSDimitry Andric #include "src/__support/macros/config.h"
15*bb722a7dSDimitry Andric #include <stddef.h> // For size_t.
16*bb722a7dSDimitry Andric 
17*bb722a7dSDimitry Andric namespace LIBC_NAMESPACE_DECL {
18*bb722a7dSDimitry Andric namespace cpp {
19*bb722a7dSDimitry Andric 
20*bb722a7dSDimitry Andric template <class T, size_t N> struct array {
21*bb722a7dSDimitry Andric   static_assert(N != 0,
22*bb722a7dSDimitry Andric                 "Cannot create a LIBC_NAMESPACE::cpp::array of size 0.");
23*bb722a7dSDimitry Andric 
24*bb722a7dSDimitry Andric   T Data[N];
25*bb722a7dSDimitry Andric   using value_type = T;
26*bb722a7dSDimitry Andric   using iterator = T *;
27*bb722a7dSDimitry Andric   using const_iterator = const T *;
28*bb722a7dSDimitry Andric   using reverse_iterator = cpp::reverse_iterator<iterator>;
29*bb722a7dSDimitry Andric   using const_reverse_iterator = cpp::reverse_iterator<const_iterator>;
30*bb722a7dSDimitry Andric 
dataarray31*bb722a7dSDimitry Andric   LIBC_INLINE constexpr T *data() { return Data; }
dataarray32*bb722a7dSDimitry Andric   LIBC_INLINE constexpr const T *data() const { return Data; }
33*bb722a7dSDimitry Andric 
frontarray34*bb722a7dSDimitry Andric   LIBC_INLINE constexpr T &front() { return Data[0]; }
frontarray35*bb722a7dSDimitry Andric   LIBC_INLINE constexpr const T &front() const { return Data[0]; }
36*bb722a7dSDimitry Andric 
backarray37*bb722a7dSDimitry Andric   LIBC_INLINE constexpr T &back() { return Data[N - 1]; }
backarray38*bb722a7dSDimitry Andric   LIBC_INLINE constexpr const T &back() const { return Data[N - 1]; }
39*bb722a7dSDimitry Andric 
40*bb722a7dSDimitry Andric   LIBC_INLINE constexpr T &operator[](size_t Index) { return Data[Index]; }
41*bb722a7dSDimitry Andric 
42*bb722a7dSDimitry Andric   LIBC_INLINE constexpr const T &operator[](size_t Index) const {
43*bb722a7dSDimitry Andric     return Data[Index];
44*bb722a7dSDimitry Andric   }
45*bb722a7dSDimitry Andric 
sizearray46*bb722a7dSDimitry Andric   LIBC_INLINE constexpr size_t size() const { return N; }
47*bb722a7dSDimitry Andric 
emptyarray48*bb722a7dSDimitry Andric   LIBC_INLINE constexpr bool empty() const { return N == 0; }
49*bb722a7dSDimitry Andric 
beginarray50*bb722a7dSDimitry Andric   LIBC_INLINE constexpr iterator begin() { return Data; }
beginarray51*bb722a7dSDimitry Andric   LIBC_INLINE constexpr const_iterator begin() const { return Data; }
cbeginarray52*bb722a7dSDimitry Andric   LIBC_INLINE constexpr const_iterator cbegin() const { return begin(); }
53*bb722a7dSDimitry Andric 
endarray54*bb722a7dSDimitry Andric   LIBC_INLINE constexpr iterator end() { return Data + N; }
endarray55*bb722a7dSDimitry Andric   LIBC_INLINE constexpr const_iterator end() const { return Data + N; }
cendarray56*bb722a7dSDimitry Andric   LIBC_INLINE constexpr const_iterator cend() const { return end(); }
57*bb722a7dSDimitry Andric 
rbeginarray58*bb722a7dSDimitry Andric   LIBC_INLINE constexpr reverse_iterator rbegin() {
59*bb722a7dSDimitry Andric     return reverse_iterator{end()};
60*bb722a7dSDimitry Andric   }
rbeginarray61*bb722a7dSDimitry Andric   LIBC_INLINE constexpr const_reverse_iterator rbegin() const {
62*bb722a7dSDimitry Andric     return const_reverse_iterator{end()};
63*bb722a7dSDimitry Andric   }
crbeginarray64*bb722a7dSDimitry Andric   LIBC_INLINE constexpr const_reverse_iterator crbegin() const {
65*bb722a7dSDimitry Andric     return rbegin();
66*bb722a7dSDimitry Andric   }
67*bb722a7dSDimitry Andric 
rendarray68*bb722a7dSDimitry Andric   LIBC_INLINE constexpr reverse_iterator rend() {
69*bb722a7dSDimitry Andric     return reverse_iterator{begin()};
70*bb722a7dSDimitry Andric   }
rendarray71*bb722a7dSDimitry Andric   LIBC_INLINE constexpr const_reverse_iterator rend() const {
72*bb722a7dSDimitry Andric     return const_reverse_iterator{begin()};
73*bb722a7dSDimitry Andric   }
crendarray74*bb722a7dSDimitry Andric   LIBC_INLINE constexpr const_reverse_iterator crend() const { return rend(); }
75*bb722a7dSDimitry Andric };
76*bb722a7dSDimitry Andric 
77*bb722a7dSDimitry Andric } // namespace cpp
78*bb722a7dSDimitry Andric } // namespace LIBC_NAMESPACE_DECL
79*bb722a7dSDimitry Andric 
80*bb722a7dSDimitry Andric #endif // LLVM_LIBC_SRC___SUPPORT_CPP_ARRAY_H
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