brainfuck, but even more painful.

brainfuckedup.js

/*----------------------*/
___=process;__$='stdin';_$_='setRawMode';_$$='on';$__='data';$_$='exit';$$_='slice';$$$=_$=>_$;___[__$][_$_]((_=>_==_)());__=(_=>(_==_)>>_)()<<(_=>(_==_)+(_==_)+(_==_)+(_==_)+(_==_)+(_==_)+(_==_)+(_==_)+(_==_)+(_==_)+(_==_)+(_==_))();$$=(_=>_>>_)();$=($=>(_=>_(_))(_=>$($=>_(_)($))))($=>_=>--_?[...$(_),(_=>_>>_)()]:[(_=>(_==_)>>_)()])(__);___[__$][_$$]($__,_$=>($$$(_$),$$$=_$=>_$));_=_=>($=>(_=>_(_))(_=>$($=>_(_)($))))($_=>([_,__])=>_==''?($[$$]?$_([__,__]):___[$_$]()):_[(_=>_>>_)()]=='+'?($[$$]==(_=>(_=>((_<<(_<<(_+(_<<_))))-_))((_==_)>>_))()?$[$$]-=$[$$]:$[$$]++,$_([_[$$_]((_=>(_==_)>>_)()),__])):_[(_=>_>>_)()]=='>'?(($$==__?$$-=$$:$$++), $_([_[$$_]((_=>(_==_)>>_)()),__])):_[(_=>_>>_)()]=='['?$[$$]?(()=>$_([($=>(_=>_(_))(_=>$($=>_(_)($))))($=>([_,__])=>_[(_=>_>>_)()]=='['?$([_[$$_]((_=>(_==_)>>_)()),++__]):_[(_=>_>>_)()]==']'?(--__ ? $([_[$$_]((_=>(_==_)>>_)()),__]):_):$([_[$$_]((_=>(_==_)>>_)()),__]))([_,(_=>_>>_)()]),__]))():$_([_[$$_]((_=>(_==_)>>_)()),__]):_[(_=>_>>_)()]=='.'?($[$$]?(___.stdout.write(String.fromCharCode($[$$])),$_([_[$$_]((_=>(_==_)>>_)()),__])):$$$=_$=>($[$$]=_$[(_=>_>>_)()],$_([_[$$_]((_=>(_==_)>>_)()),__]))):$_)([_,_]);
/*--- CODE ENDS HERE ---*/

// usage:
_('>..');

// brainfuckedup operates on a type of 4096 cells, where each cell is an unsigned 8 bit number
// on startup, the tape is filled with 0s, except the currently selected cell, which is a 1
// the entire program is wrapped in a `while(CELLS[CURRENT])`
//   +   increment current cell
//   >   move right one cell
//   .   current cell is?
//       |- nonzero -> print out as ASCII
//       `-    zero -> take a single ASCII character as input
// [...] current cell is?
//       |- nonzero -> execute code inbetween
//       `-    zero -> skip code inbetween