CTX_sysMultiArityConcat : CONTEXT =
BEGIN
  
  STATE : TYPE =
    [# inst_src1 : CTX_RegUN{3}!STATE
     , inst_src2 : CTX_RegUN{4}!STATE
     , inst_src3 : CTX_RegUN{5}!STATE
     , inst_snk : CTX_RegUN{12}!STATE
     #] ;
  
  ctor : STATE =
    (# inst_src1 := CTX_RegUN{3}!ctor
     , inst_src2 := CTX_RegUN{4}!ctor
     , inst_src3 := CTX_RegUN{5}!ctor
     , inst_snk := CTX_RegUN{12}!ctor
     #) ;
  
  rule_RL_d (state0 : STATE) : [ BOOLEAN, STATE ] =
    LET def__read__h44 : Bit{3}!T = CTX_RegUN{3}!meth_read(state0.inst_src1)
    IN LET def__read__h76 : Bit{4}!T = CTX_RegUN{4}!meth_read(state0.inst_src2)
    IN LET def__read__h108 : Bit{5}!T = CTX_RegUN{5}!meth_read(state0.inst_src3)
    IN LET act1 : [ CTX_RegUN{12}!STATE, Unit!T ] =
	     CTX_RegUN{12}!meth_write(Prim2{3,9}!primConcat(def__read__h44,
							    Prim2{4,5}!primConcat(def__read__h76, def__read__h108)),
				      state0.inst_snk)
    IN LET state1 : STATE = state0 WITH .inst_snk := act1.1
    IN ( TRUE, state1 ) ;
  
END