input_name_to_input_target

The target for a mapping-string name such as leftx or dpup, or .UNINITIALIZED for an unknown name.

assert(input_name_to_input_target("start") == .START);
assert(input_name_to_input_target("nope") == .UNINITIALIZED);

input_name_to_input_target :: (name: string) -> SDL_Input_Target