Bug 7587 – reduce() of a const array of tuples too

import std.algorithm, std.typecons; int add1(int x, int y) { return x + y; } alias Tuple!int T; T add2(T x, T y) { return T(x[0] + y[0]); } void main() { T[] items1 = [T(0), T(1)]; const t0 = T(0); immutable r1 = reduce!add2(t0, items1); // OK const(int[]) items2 = [0, 1]; const int zero = 0; immutable r2 = reduce!add1(zero, items2); // OK const(T[]) items3 = items1.idup; immutable r3 = reduce!add2(t0, items3); // Error } DMD 2.059head gives: ...\dmd2\src\phobos\std\typecons.d(399): Error: template std.typecons.Tuple!(int).Tuple.opAssign(R) if (isTuple!(R) && allSatisfy!(isIdentityAssignable,Types)) does not match any function template declaration ...\dmd2\src\phobos\std\typecons.d(399): Error: template std.typecons.Tuple!(int).Tuple.opAssign(R) if (isTuple!(R) && allSatisfy!(isIdentityAssignable,Types)) cannot deduce template function from argument types !()(const(int)) ...\dmd2\src\phobos\std\algorithm.d(702): Error: template instance std.typecons.Tuple!(Tuple!(int)).Tuple.__ctor!(const(Tuple!(int))) error instantiating test.d(17): instantiated from here: reduce!(const(Tuple!(int)),const(Tuple!(int)[])) test.d(17): Error: template instance std.algorithm.reduce!(add2).reduce!(const(Tuple!(int)),const(Tuple!(int)[])) error instantiating I think just as reduce works on an const(int[]) it should also work on an const(Tuple!(int)[]).

This appears to have been fixed in 2.061 although I can't find exactly where.

Changed to WORKSFORME so that it doesn't appear in the changelog for next update.