Switching rows with columns

[via Digitalmars-d-learn]

On Saturday, 4 July 2015 at 16:29:44 UTC, Marc Schütz wrote:
> Try std.range.transposed:
> http://dlang.org/phobos/std_range.html#.transposed

Does this work with user-defined types?

I defined two structs that implement the InputRange(possibly 
ForwardRange) interface, an integer range and a range of those 
integer ranges.

DMD tells me the "transposed" template cannot deduce function 
from the arguments, which is a range of integer ranges.
The template does, however, work on a two-dimensional array.

The "save" method is implemented using a simple "return this", 
could this be to blame?