Seastar
High performance C++ framework for concurrent servers
array_map.hh
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18 /*
19  * Copyright (C) 2014 Cloudius Systems, Ltd.
20  */
21 
22 #pragma once
23 
24 #ifndef SEASTAR_MODULE
25 #include <array>
26 #include <cstddef>
27 #include <stdexcept>
28 #include <string>
29 #include <utility>
30 #include <seastar/util/modules.hh>
31 #endif
32 
33 namespace seastar {
34 
35 // unordered_map implemented as a simple array
36 
37 SEASTAR_MODULE_EXPORT
38 template <typename Value, size_t Max>
39 class array_map {
40  std::array<Value, Max> _a {};
41 public:
42  array_map(std::initializer_list<std::pair<size_t, Value>> i) {
43  for (auto kv : i) {
44  _a[kv.first] = kv.second;
45  }
46  }
47  Value& operator[](size_t key) { return _a[key]; }
48  const Value& operator[](size_t key) const { return _a[key]; }
49 
50  Value& at(size_t key) {
51  if (key >= Max) {
52  throw std::out_of_range(std::to_string(key) + " >= " + std::to_string(Max));
53  }
54  return _a[key];
55  }
56 };
57 
58 }
Definition: array_map.hh:39
Seastar API namespace.
Definition: abort_on_ebadf.hh:26