Add allocator::wrap.

lib/std/core/allocators/arena_allocator.c3

@@ -31,6 +31,11 @@ struct ArenaAllocatorHeader @local
 	char[?] data;
 }
 
+macro ArenaAllocator* wrap(char[] bytes)
+{
+	return ArenaAllocator{}.init(bytes);
+}
+
 <*
  @require ptr != null
 *>

releasenotes.md

@@ -77,6 +77,7 @@
 - Added weakly linked `fmodf`.
 - Add `@select` to perform the equivalent of `a ? x : y` at compile time.
 - `HashMap` is now `Printable`.
+- Add `allocator::wrap` to create an arena allocator on the stack from bytes.
 
 ## 0.6.6 Change list