This isn’t better than an elseif chain, inside a function passed to this switch module it cannot return to the function where the switch was called, it cannot break out or continue a loop which the switch is used in, and it cannot use the vararg from the function in which the switch was called from. This module also uses if, so what is the benefit? Just avoiding elseif chains doesn’t seem like a reason to use something like this, considering it must allocate a temporary object to do the switch (and later free that temporary object) and the previously mentioned things which are impossible inside of an inner function.
If mapping values using a Lua table doesn’t work, then using an array and table.find should work (because it uses __eq) fine.
Also, what is the problem with elseif chains?