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  1. #include <iostream>
  2. #include <vector>
  3.  
  4. template < typename Derived, typename R, typename T >
  5. struct cascade_call_base {
  6.  
  7.     typedef R result_type;
  8.  
  9.     typedef T param_type;
  10.     typedef param_type const & param_ref;
  11.  
  12.     typedef std::vector<param_type> params_type;
  13.     typedef params_type const & params_ref;
  14.  
  15.     struct param_packer {
  16.         Derived & callee;
  17.         params_type params;
  18.  
  19.         param_packer( Derived & callee, param_ref first ) 
  20.         : callee(callee), params( 1, first )
  21.         { }
  22.  
  23.         param_packer& operator,( param_ref append ) {
  24.             params.push_back( append );
  25.             return *this;
  26.         }
  27.  
  28.         operator result_type() {
  29.             return callee.invoke( params );
  30.         }
  31.     };
  32.  
  33.     param_packer
  34.     operator,( param_ref first ) {
  35.         return param_packer( static_cast<Derived&>(*this), first );
  36.     }
  37. };
  38.  
  39. struct Test : cascade_call_base<Test,int,int> {
  40.     result_type  
  41.     invoke( params_ref params ) {
  42.         return params.size();
  43.     }
  44. } test;
  45.  
  46. int main() {
  47.  
  48.     using namespace std;
  49.  
  50.     cout << (test,1,2,3) << endl;
  51.     cout << (test,4,5) << endl;
  52. }
Success #stdin #stdout 0s 3028KB
comments (?)
stdin 
Standard input is empty
stdout 
3
2
https://ideone.com/biG05U
language:
C++ (gcc 8.3)
created:
12 years ago
visibility:
public

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