One more nasty design of C++'s name lookup
As we all know that C++’s name lookup has always been extremely counter-intuitive. The infamous argument-dependent lookup (ADL), for example, often leads to unexpected behavior and, worse yet, is often difficult to troubleshoot. This can happen when you define a function in your current namespace, but when you call it the compiler selects another function with the same name thousands of miles away, even though you did not using that foreign function in the current namespace....