diff --git a/docs/grammar.abnf b/docs/grammar.abnf
index f2a7284..3934a92 100644
--- a/docs/grammar.abnf
+++ b/docs/grammar.abnf
@@ -1,8 +1,10 @@
 ; Rutile's grammar formal definition in ABNF
-; NOTE: terminal strings are case sensitive here
+; NOTES:
+;   - terminal strings are by default case sensitive
+;   - alternatives are ordered
 
 function-kind 	 = "proc" / "iter"
-proc-decl 		 = function-kind "(" [proc-decl-args] ")" [ident] *stmt 'end'
+proc-decl 		 = function-kind "(" [proc-decl-args] ")" ":" [ident] *stmt 'end'
 proc-decl-args 	 = symbol-type-pair *("," symbol-type-pair)
 symbol-type-pair = ident ":" ident
 
@@ -15,9 +17,9 @@ funcargs      = expr-list
 array-literal = "[" expr-list "]"
 
 expr-list 	= expr *("," expr) [","]					; Allows a trailling comma
-expr 		=  number
-expr		=/ array-literal
-expr		=/ function-call
+expr 		= number
+			/ array-literal
+			/ function-call
 
 pragma = "#" "["  "]"								; TODO
 decorated-decl = pragma (proc-decl / symbol-decl)
@@ -29,24 +31,24 @@ break-expr 		= "break" *expr
 return-stmt 	= "return" *expr
 yield-stmt 		= "yield" *expr
 loop-control 	= "next" / break-expr
-stmt 			=  proc-decl
-stmt 			=/ expr
-stmt 			=/ loop-control
-stmt 			=/ if-expr
-stmt 			=/ while-stmt
-stmt 			=/ return-stmt
-stmt 			=/ yield-stmt
+stmt			= proc-decl
+				/ expr
+				/ loop-control
+				/ if-expr
+				/ while-stmt
+				/ return-stmt
+				/ yield-stmt
 
 ident = (ALPHA / "_") *(ALPHA / DIGIT / "_" / "?" / "!")
 ; Identifier accounting for namespacing: std:io.print, aaa:bbb:ccc
 ident-qualified = (ALPHA / "_") *(ALPHA / DIGIT / "_" / "?" / "!" / ":" / ".")
 
+OCTDIGIT = %x30-37
 number 	= 1*DIGIT				; Decimal
 		/ "0b" 1*("0" / "1")	; Binary
-		/ "0o" 1*(0-8)			; Octal
+		/ "0o" 1*OCTDIGIT		; Octal
 		/ "0x" 1*HEXDIGIT 		; Hexadecimal
 
-byte			= %x00-FF
 escape 			= "\" ("\" / DQUOTE / "0" / "a" / "b" / "n" / "r" / "t" / ("x" 1*2HEXDIGIT))
-character		= byte / escape
+character		= OCTET / escape
 string-literal 	= DQUOTE *character DQUOTE