# Evaluate `args` as expressions in the call of `mpropdef` on `recv`.
	# This method is used to manage varargs in signatures and returns the real array
	# of instances to use in the call.
	# Return `null` if one of the evaluation of the arguments return null.
	fun varargize(mpropdef: MMethodDef, map: nullable SignatureMap, recv: Instance, args: SequenceRead[AExpr]): nullable Array[Instance]
	do
		var msignature = mpropdef.msignature.as(not null)
		var res = new Array[Instance]
		res.add(recv)

		if msignature.arity == 0 then return res

		if map == null then
			assert args.length == msignature.arity else debug("Expected {msignature.arity} args, got {args.length}")
			var rest_args = aexprs_to_instances(args.iterator)
			if rest_args == null then return null
			res.append(rest_args)
			return res
		end

		# Eval in order of arguments, not parameters
		var exprs = aexprs_to_instances(args.iterator)
		if exprs == null then return null

		# Fill `res` with the result of the evaluation according to the mapping
		for i in [0..msignature.arity[ do
			var param = msignature.mparameters[i]
			var j = map.map.get_or_null(i)
			if j == null then
				# default value
				res.add(null_instance)
				continue
			end
			if param.is_vararg and args[i].vararg_decl > 0 then
				var vararg = exprs.sub(j, args[i].vararg_decl)
				var elttype = param.mtype.anchor_to(self.mainmodule, recv.mtype.as(MClassType))
				var arg = self.array_instance(vararg, elttype)
				res.add(arg)
				continue
			end
			res.add exprs[j]
		end
		return res
	end