Lexing c-comments using camlp4

lexer.ml

type token = 
  | Text of char
  | Comment of string

let rec lex = parser
	| [< ''/'; p = parser (* left factoring... *)
		| [< ''/'; stream >] ->
			let buffer = Buffer.create 1 in
				lex_comment buffer stream
		| [< ''*'; stream >] ->
			let buffer = Buffer.create 1 in
				lex_multi_comment buffer stream
		>] -> p
	| [< 'c; stream >] ->
		[< 'Text c; lex stream >]
	| [< >] -> [< >]
and lex_comment buffer = parser
	| [< ' ('\n'); stream=lex >] ->
		[< 'Comment (Buffer.contents buffer); stream >]
	| [< 'c; stream >] ->
		Buffer.add_char buffer c;
		lex_comment buffer stream
and lex_multi_comment buffer = parser
	| [< ''*'; ''/'; stream=lex >] ->
		[< 'Comment (Buffer.contents buffer); stream >]
	| [< 'c; stream >] ->
		Buffer.add_char buffer c;
		lex_multi_comment buffer stream
;;