fmap.cpp

//
// Created by light on 20-1-5.
//

#include <iostream>
#include <vector>

using namespace std;

template <template <typename, typename> class OutContainer = vector, typename F,
          class R>
auto fmap(F &&f, R &&inputs) {
  typedef decay_t<decltype(f(*inputs.begin()))> result_type;

  OutContainer<result_type, allocator<result_type>> result;

  for (auto &&item : inputs) {
    result.push_back(f(item));
  }
  return result;
}

// 对每一个数进行加1操作
int add_1(int x) { return x + 1; }

int main() {
  vector<int> v{1, 2, 3, 4, 5};
  auto result = fmap(add_1, v);

  for (auto item : result)
    cout << item << " ";
  cout << endl;
  return 0;
}