mono ? might be worth looking into the interpreter from it at least.c# would be an acceptable compromise, although I am not aware of the effort involved to implement/embed an interpreter. I don't know of any available runtime (not even considering legal aspects here).
QC might not cut it for an engine as advanced as idtech 4 atleast if you want to take advantage of all it's capabilities, sure it could probably be done but you might end up regretting it afterwards because it would be an unholy mess even if support could be hacked in. That said it could probably be cool for something like the mini games inside Doom3
or something similar to wolfenstein the new order where you could play levels from the old wolfenstein. A remake of quake in this engine would rock and then we could throw in the old version as a minigame 
. Maybe something for bethesda to ponder on hmm ????
It would be a new era as programming language on its own! A language that fired up my passion for programming, so, I'm pretty devoted to it! 
), but personally I don't have any complaints to do to FTE and fteqcc. I love working with them and, imho, qc language it's not its weaking point. It lacks serious good mesh collision control, a personal physics engine (ODE support is too crashy to be considered usable) and a new rendering engine.
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