Simen kjaeraas napisał: > Tomek Sowiński <j...@ask.me> wrote: > >> __traits(getAttribute, opIn, @complexity).bigOh == O.constant > > How does this test for things like N log M? > > __traits(getAttribute, opIn, @complexity).bigOh == tuple( O.linear, > O.logarithmic )
Or: __traits(getAttribute, opIn, @complexity).bigOh = O.linear * O.log bigOh could be e.g. a struct with an overloaded multiplier. But you brought up something interesting -- how to bind N, M with different properties of function arguments; big oh expressions can get quite complex, e.g. void completeSort(alias less = "a < b", SwapStrategy ss = SwapStrategy.unstable, Range1, Range2)(SortedRange!(Range1,less) lhs, Range2 rhs); "[...] Performs Ο(lhs.length + rhs.length * log(rhs.length)) (best case) to Ο((lhs.length + rhs.length) * log(lhs.length + rhs.length)) (worst-case) evaluations of swap." Even if the attribute properties could see the arguments, how to deal with things like lhs.length + rhs.length? It has to be inspectable at compile-time. One idea is to store the expression's abstract syntax tree (we want AST macros in D3 anyway)... But I got a feeling we're heading for an overkill :) -- Tomek
