func New(in io.Reader, filename string) *Parser {
ret := new(Parser)
ret.filename = filename
ret.lx = lexer.New(in, filename)
ret.s = lexin.NewScanner(ret.lx, isComment)
return ret
}
func mainLex(args []string) {
fset := flag.NewFlagSet("leaf-lex", flag.ExitOnError)
fset.Parse(args)
files := fset.Args()
if len(files) == 0 {
fmt.Fprintln(os.Stderr, "no input file.")
return
}
onError := func(e error) {
if e != nil {
fmt.Fprintln(os.Stderr, e)
}
}
for _, f := range files {
fmt.Printf("[%s]\n", f)
fin, e := os.Open(f)
if e != nil {
onError(e)
continue
}
lex := lexer.New(fin, f)
lex.OnError(onError)
for lex.Scan() {
tok := lex.Token()
fmt.Println(tok.String())
}
onError(fin.Close())
}
}