LINQ like query in c++
A more lazy way of selecting objects from a container
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| #include <deque> | |
| template <class T> | |
| class table | |
| { | |
| public: | |
| table<T> select (const auto& where) | |
| { | |
| table results; | |
| for(auto t : rows) if (where(t)) results.insert(t); | |
| return results; | |
| } | |
| void insert(const T& _record) {rows.push_back(_record);} | |
| std::deque<T> rows; | |
| }; | |
| #define where(x,w) [](auto& x) { return w; } | |
| int main() | |
| { | |
| struct record | |
| { | |
| int id; | |
| float value; | |
| }; | |
| table<record> records; | |
| records.insert({1,1.123}); | |
| records.insert({2,2.234}); | |
| records.insert({3,3.345}); | |
| auto results = records.select( where(r, r.id==2) ); | |
| return results.rows[0].id; | |
| } |
