bearophile Wrote: >> (time ago I have suggested for a compile time flag that's defined inside >> functions to know if their result is used, to avoid computing it in some >> situations, turning the single function in a kind of templated function, but >> I am not sure it can work well if you have function pointers. So you need a >> single entry point for two functions). > qwerty: > > For a function without any side effects, it shouldn't be a problem.. I > > think :) > > Ignoring the return value of a function without side effects (in D2 pure > functions or nothrow pure functions) has to be an error. I even have a bug > report for this, because it's the same situation as an expression like: > a + 5; > that the compiler sees as an error. > I meant this:
function is with side effects --> normal func() function is without side effect --> generate 2 version of the function *if compiler can see no return is required --> point to noReturnCalc version if compiler doesn't know --> point to returnCalc version if called through pointer --> point to returnCalc version As the function has no side effect, it doesn't matter there are two different versions (no static members etc.) This will only speed up the * Hope it makes any sense :D
