December 04, 2008 Auto return type | ||||
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The D2 docs say: "Function templates can have their return types deduced based on the first ReturnStatement in the function:". This is a little example, that also shows a closure at work: import std.stdio: putr = writefln; auto make_counter()(int start_num) { int start = start_num; return { return start++; }; } void main() { auto from_ten = make_counter(10); auto from_three = make_counter(3); putr(from_ten()); // 10 putr(from_ten()); // 11 putr(from_three()); // 3 putr(from_ten()); // 12 putr(from_three()); // 4 } I think it can be useful for the a future version of D2 if also normal functions allow such return type inference: auto make_counter(int start_num) { ... In the current D2 how you can turn that function template make_counter into an actual function? Bye, bearophile |
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