In SortedRange, there is a debug clause in the constructor which checks the sortedness of the input.

The final assert assumes it can print the range if the sortedness isn't true.  However, a range of types that do not define toString will fail to compile, even if the range can be sorted.

For example:

interface I {}

auto sr = SortedRange!(I[]);

The fix is simple, do the assert without printing the range (from range.d line 5400 in dmd 2.052):


-            assert(isSorted!pred(st), text(st));
+            static if(is(typeof(text(st))))
+                assert(isSorted!pred(st), text(st));
+            else
+                assert(isSorted!pred(st));

This is another case of bug 4901, but I didn't see it because I normally don't compile with -debug enabled.

See http://www.dsource.org/projects/dcollections/ticket/13 for the error listing.