diff --git a/jortsc/parser/parser.py b/jortsc/parser/parser.py
index 6143f14..47410a2 100644
--- a/jortsc/parser/parser.py
+++ b/jortsc/parser/parser.py
@@ -18,13 +18,14 @@ QUOTE: "\\""
 
 identifier: WHITESPACE* ANY WHITESPACE*
 
-single_comment: "//" ANY* NEWLINE
+single_comment: SINGLE_COMMENT ANY* NEWLINE
 multi_comment: COM_START ANY* COM_END
 
 import_stmt: IMPORT identifier NEWLINE
 
 fn_arg: identifier identifier
-fn_stmt: FN identifier? "(" [fn_arg COMMA] ")" [ARROW identifier] "{" [stmt NEWLINE]* "}"
+parameters: fn_arg (COMMA fn_arg)
+fn_stmt: FN identifier? "(" parameters? ")" [ARROW identifier] "{" NEWLINE? [stmt NEWLINE]* "}"
 
 sign_int: "+" | "-"
 string: QUOTE ANY* QUOTE
@@ -32,9 +33,9 @@ value: (sign_int* INTEGER) | string
 
 call_stmt: [identifier DOT] identifier "(" [value COMMA]* ")"
 
-stmt: (NEWLINE*) | import_stmt | fn_stmt | call_stmt
+stmt: value | import_stmt | fn_stmt | call_stmt
 
-start: (stmt NEWLINE)*
+start: (NEWLINE | stmt)*
 """
 
 def parse(string: str):