init {
	constant := 10
	variable := 10
	ans := 20
}

channel changeVar {
	out variable(cur: Int, change(next: Int)) = next
}

channel changeConst {
	out constant(const: Int, change(next: Int)) = next
}

channel calcAns {
	in variable(curVar: Int, calc(const: Int, nextVar: Int)) = nextVar
	ref constant(const: Int, calc(const: Int, var: Int))
	out ans(curAns: Int, calc(const: Int, var: Int)) = var + const
}