Hash maps now copy keys if keys are copyable.

lib/std/core/mem.c3

@@ -177,19 +177,14 @@ macro bool equals(a, b, isz len = -1, usz $align = 0)
 	return true;
 }
 
-macro @clone(&value) @builtin
+macro @clone(&value, Allocator *using = mem::heap()) @builtin
 {
-	$typeof(value)* x = malloc($typeof(value));
+	$typeof(value)* x = malloc($typeof(value), .using = using);
 	*x = value;
 	return x;
 }
 
-macro @tclone(&value) @builtin
-{
-	$typeof(value)* x = talloc($typeof(value));
-	*x = value;
-	return x;
-}
+macro @tclone(&value) @builtin => @clone(value, mem::temp());
 
 macro type_alloc_must_be_aligned($Type)
 {

lib/std/core/string.c3

@@ -346,6 +346,12 @@ fn String String.copy(s, Allocator* using = mem::heap())
 	str[len] = 0;
 	return (String)str[:len];
 }
+fn void String.free(&s, Allocator* using = mem::heap())
+{
+	if (!s.len) return;
+	mem::free(s.ptr, .using = using);
+	*s = "";
+}
 
 fn String String.tcopy(s) => s.copy(mem::temp()) @inline;
 

lib/std/core/types.c3

@@ -229,6 +229,14 @@ macro bool is_equatable_type($Type)
 	$endif
 }
 
+/**
+ * Checks if a type implements the copy protocol.
+ **/
+macro bool implements_copy($Type)
+{
+	return $checks(Allocator *a, $Type x, $Type y = x.copy(a), $Type z = x.copy(), z.free(a), z.free());
+}
+
 macro bool is_equatable_value(value)
 {
 	return is_equatable_type($typeof(value));