This D2 program looks correct:


import std.typecons: Tuple;
void main() {
    auto t = Tuple!(int)(1);
}



But DMD v2.046 prints at compile-time:

...\src\phobos\std\typecons.d(349): Error: no property 'Types' for type 'int'
Error: no property 'length' for type 'int'
...\src\phobos\std\typecons.d(349): Error: static assert  (0u == 1u) is false
test.d(3):        instantiated from here: __ctor!(int)


If tuples don't support a single item, then the docs have to say it, and it's better to produce a better error message.