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  1.     #include <functional>
  2.     #include <vector>
  3.     #include <iostream>
  4.  
  5.     using std::cout;
  6.     using std::endl;
  7.  
  8.     struct S {
  9.         std::function< void() > func;
  10.         //S( std::function< void() > && f ) : func( f ) {}
  11.     };
  12.  
  13.     void foo( const S & s ) {
  14.         if ( s.func ) {
  15.             cout << "ok : ";
  16.             s.func();
  17.         }
  18.         else {
  19.             cout << "fail" << endl;
  20.         }
  21.     }
  22.  
  23.     void bar_i( int i ) { cout << i << endl; }
  24.     void bar( std::vector< int > i ) { cout << i[ 0 ] << endl; }
  25.  
  26.     int main() {
  27.         foo( S{ std::bind( bar_i, 1 ) } );
  28.         S s_i{ std::bind( bar_i, 2 ) };
  29.         foo( s_i );
  30.  
  31.         std::vector< int > one = { 42 };
  32.         foo( S{ std::bind( bar, one ) } );
  33.         S s{ std::bind( bar, one ) };
  34.         foo( s );
  35.  
  36.     }
  37.  
Success #stdin #stdout 0s 3472KB
comments (?)
stdin 
Standard input is empty
stdout 
ok : 1
ok : 2
ok : 42
ok : 42
https://ideone.com/LIjKCT
language:
C++14 (gcc 8.3)
created:
8 years ago
visibility:
public

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