isSortedRange

import std.algorithm: sort;
import std.range: assumeSorted;
static assert(isSortedRange!(typeof([0, 1, 2])) == false);
static assert(isSortedRange!([0, 1, 2].sort) == true);
static assert(isSortedRange!(typeof([0, 1, 2].assumeSorted)) == true);
static assert(isSortedRange!int == false);