diff --git a/ssc/ast/nodes.functions.cs b/ssc/ast/nodes.functions.cs
index 2bb88ad..146ec79 100644
--- a/ssc/ast/nodes.functions.cs
+++ b/ssc/ast/nodes.functions.cs
@@ -61,12 +61,7 @@ namespace arookas {
 		public sunParameterInfo ParameterInfo { get { return new sunParameterInfo(Parameters, IsVariadic); } }
 
 		public sunParameterList(sunSourceLocation location)
-			: base(location) {
-			var count = this.Count(i => i is sunEllipsis);
-			if (count > 1 || (count > 0 && !(this[Count - 1] is sunEllipsis))) {
-				throw new sunVariadicParameterListException(this);
-			}
-		}
+			: base(location) { }
 	}
 
 	class sunEllipsis : sunNode {
diff --git a/ssc/parser.cs b/ssc/parser.cs
index 5595cbb..e7579c3 100644
--- a/ssc/parser.cs
+++ b/ssc/parser.cs
@@ -52,9 +52,7 @@ namespace arookas {
 					case __sunConstants.BINARY_OPERATOR:
 					case __sunConstants.UNARY_OPERATOR:
 					case __sunConstants.AUGMENT_OPERATOR:
-					case __sunConstants.TERM:
-					case __sunConstants.PARAMETER:
-					case __sunConstants.ARGUMENT: {
+					case __sunConstants.TERM: {
 							return ast[0];
 						}
 				}
@@ -176,9 +174,7 @@ namespace arookas {
 				case __sunConstants.FUNCTION_CALL: return new sunFunctionCall(location);
 
 				case __sunConstants.PARAMETER_LIST: return new sunParameterList(location);
-				case __sunConstants.PARAMETER: return new sunNode(location);
 				case __sunConstants.ARGUMENT_LIST: return new sunNode(location);
-				case __sunConstants.ARGUMENT: return new sunNode(location);
 			}
 
 			// variables
diff --git a/ssc/sunscript.grammar b/ssc/sunscript.grammar
index b63ddb3..e23a97c 100644
--- a/ssc/sunscript.grammar
+++ b/ssc/sunscript.grammar
@@ -193,10 +193,8 @@ prefix_augment						= augment_operator IDENTIFIER;
 function_definition				= FUNCTION IDENTIFIER parameter_list statement_block;
 function_call							= IDENTIFIER argument_list;
 
-parameter_list						= L_PAREN [parameter {COMMA parameter}] R_PAREN; // e.g. (a, b, ...)
-parameter									= IDENTIFIER | ELLIPSIS;
-argument_list							= L_PAREN [argument {COMMA argument}] R_PAREN;
-argument									= expression;
+parameter_list						= L_PAREN [IDENTIFIER {COMMA IDENTIFIER} [COMMA ELLIPSIS] | ELLIPSIS] R_PAREN; // e.g. (a, b, ...)
+argument_list							= L_PAREN [expression {COMMA expression}] R_PAREN;
 
 // builtins
 builtin_declaration				= BUILTIN IDENTIFIER parameter_list;