Is it possible to use a button for a combo but also by itself?

[madprops]

I'm reserving button B on my usb controller to work as a mod key for combos, like b + stick, or b + pad-down, etc. But I'm wondering if it's possible to also map when I simply tap B by itself. I want to map it to key(KEY_ESC). I tried if_tap, and if_single. The thing is that it won't allow the injection at all on single button B, I guess because of the other combos.