language: C++11 (gcc-4.7.2)
date: 763 days 14 hours ago
link:
visibility: private 
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#include <functional>
#include <iostream>
 
int main(){
  using namespace std;
  using namespace placeholders;
  // no argument binding, both are equivalent, both return opposite of input
  auto neg_lambda = [](bool b){ return !b; };
  // could do:
//function<bool(bool)> neg_func = neg_lambda;
  function<bool(bool)> neg_func = [](bool b){ return !b; };
 
  // with argument binding, always returns true
  // could do:
//function<bool()> true_func(bind(neg_func,false));
  function<bool()> true_func(bind(neg_lambda,false));
 
  cout << boolalpha << "booleans:\n";
 
  cout << "unbound...\n\t"
       << neg_lambda(true) << "\n\t"
       << neg_func(true) << "\n"
       << "bound...\n\t"
       << true_func() << "\n";
 
  // more complicated, will add the parameters
  auto add_lambda = [](int a, int b){ return a+b; };
  // could do:
//function<int(int,int)> add_func = add_lambda;
  function<int(int,int)> add_func = [](int a, int b){ return a+b; };
 
  // with argument binding, always adds 5
  // could do:
//function<int(int)> add5_func(bind(add_func,5,_1));
  function<int(int)> add5_func(bind(add_lambda,5,_1));
 
  cout << "additions:\n\t"
       << add_lambda(10,20) << "\n\t"
       << add_func(10,20) << "\n"
       << "add 5:\n\t"
       << add5_func(7);
}