std::set<Key,Compare,Allocator>::value_comp
From cppreference.com
std::set::value_compare value_comp()const; | ||
Returns the function object that compares the values. It is the same as key_comp.
Contents |
[edit]Parameters
(none)
[edit]Return value
The value comparison function object.
[edit]Complexity
Constant.
[edit]Example
Run this code
#include <iostream>#include <set>#include <utility> // Example module 97 key compare functionstruct ModCmp {bool operator()(int lhs, int rhs)const{return(lhs %97)<(rhs %97);}}; int main(){std::set<int, ModCmp> cont{1, 2, 3, 4, 5}; // Same behaviour as key_comp()auto comp_func = cont.value_comp(); for(constint val{100};constint key : cont){constbool before = comp_func(key, val);constbool after = comp_func(val, key); std::cout<<"Key ("<< key <<") ";if(!before &&!after)std::cout<<"equivalent to key ("<< val <<")\n";elseif(before)std::cout<<"goes before key ("<< val <<")\n";elseif(after)std::cout<<"goes after key ("<< val <<")\n";elsestd::unreachable();}}
Output:
Key (1) goes before key (100) Key (2) goes before key (100) Key (3) equivalent to key (100) Key (4) goes after key (100) Key (5) goes after key (100)
[edit]See also
| returns the function that compares keys (public member function) |
