preprocessor_lexer.mll

{ open Parser }

(* handle windows newlines *)
let eol = '\r'? '\n'
(* state variables: line number, etc. *)
let line_num = ref 1

(* the basic text eater *)
(* we save all the characters that we see, 
 we encounter the preprocessor starter *)
rule token = parse
	| '#'        { preprocessor_token lexbuf }
	| eol        { incr line_num; token lexbuf }
	| eof        { EOF }
	| _ as c     { TEXT(c) }

(* The actual preprocessor tokens *)
(* Here, we see that we just capture
string expressions, dot-delimeted ident names,
macro continuation lines and more *)
and preprocessor_token = parse
	| "import"            { IMPORT }
	| "strings"           { STRINGS }
	| '"'(_* as s)'"'     { STRING(s) }
	| '.'                 { DOT }
	| ident               { IDENTIFIER(s) }
	| eol '#'             { incr line_num; CONTINUE }
	| eol | eof           { EOF; token lexbuf }