I forgot about commas

src/parser/parser.c

@@ -1165,7 +1165,7 @@ static inline ResultType(Nothing, charptr) parseLambda(SolsParser* parser) {
             return Error(Nothing, charptr, type.as.error);
         }
 
-        // Pattern of type, name
+        // Pattern of type, name, comma
 
         SolsType tmpType;
 
@@ -1191,6 +1191,19 @@ static inline ResultType(Nothing, charptr) parseLambda(SolsParser* parser) {
         // Add type to constructed SolsType
         addChildToSolsType(&type.as.success, tmpType, argName);
         parserConsume(parser);
+
+        next = parserPeek(parser, 1);
+        if (next.error) {
+            return Error(Nothing, charptr, "Expecting a comma or closing bracket");
+        }
+        if (next.as.success.type == STT_CLOSE_PAREN) {
+            parserConsume(parser);
+            break;
+        }
+        if (next.as.success.type != STT_COMMA) {
+            return Error(Nothing, charptr, "Expecting a comma or closing bracket");
+        }
+        parserConsume(parser);
     }
 
     // Parse type at the end