51 lines
1.4 KiB
C++
51 lines
1.4 KiB
C++
// functor.cpp -- using a functor
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#include <iostream>
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#include <list>
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#include <iterator>
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#include <algorithm>
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template<class T> // functor class defines operator()()
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class TooBig
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{
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private:
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T cutoff;
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public:
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TooBig(const T & t) : cutoff(t) {}
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bool operator()(const T & v) { return v > cutoff; }
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};
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void outint(int n) {std::cout << n << " ";}
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int main()
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{
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using std::list;
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using std::cout;
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using std::endl;
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using std::for_each;
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using std::remove_if;
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TooBig<int> f100(100); // limit = 100
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int vals[10] = {50, 100, 90, 180, 60, 210, 415, 88, 188, 201};
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list<int> yadayada(vals, vals + 10); // range constructor
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list<int> etcetera(vals, vals + 10);
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// C++0x can use the following instead
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// list<int> yadayada = {50, 100, 90, 180, 60, 210, 415, 88, 188, 201};
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// list<int> etcetera {50, 100, 90, 180, 60, 210, 415, 88, 188, 201};
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cout << "Original lists:\n";
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for_each(yadayada.begin(), yadayada.end(), outint);
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cout << endl;
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for_each(etcetera.begin(), etcetera.end(), outint);
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cout << endl;
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yadayada.remove_if(f100); // use a named function object
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etcetera.remove_if(TooBig<int>(200)); // construct a function object
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cout <<"Trimmed lists:\n";
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for_each(yadayada.begin(), yadayada.end(), outint);
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cout << endl;
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for_each(etcetera.begin(), etcetera.end(), outint);
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cout << endl;
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// std::cin.get();
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return 0;
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}
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