Zig Academy · Lesson

errdefer for Failure Cleanup

Undo work only when something fails.

Cleanup Only on Failure

Sometimes you must undo work when an operation fails, but keep it when it succeeds. That precise case is what errdefer is for.

An errdefer schedules code to run as the scope exits, but only when the function returns an error from that point onward.

errdefer allocator.free(buffer);