an associative array
Complexity: O(m), where m is the number of (key, value) pairs in the associative array.
import std.algorithm.comparison : equal; auto h = Hashtable!(int, int)([1 : 10]); assert(equal(h.keys(), [1])); assert(equal(h.values(), [10]));
Constructs a qualified hashtable out of an associative array. Because no allocator was provided, the hashtable will use the GCAllocator.std.experimental.allocator.gc_allocator..