Ejemplo n.º 1
0
func main() {

	short := "hp:"
	long := []string{
		"help",
		"pattern=",
	}

	_, optargs, err := getopt.GetOpt(os.Args[1:], short, long)
	if err != nil {
		log.Print(os.Stderr, err)
		Usage(1)
	}

	patterns := make([]string, 0, 10)
	for _, oa := range optargs {
		switch oa.Opt() {
		case "-h", "--help":
			Usage(0)
		case "-p", "--pattern":
			patterns = append(patterns, oa.Arg())
		}
	}

	if len(patterns) <= 0 {
		log.Print("Must supply some regulars expressions!")
		Usage(1)
	}

	asts := make([]frontend.AST, 0, len(patterns))
	for _, p := range patterns {
		ast, err := frontend.Parse([]byte(p))
		if err != nil {
			log.Fatal(err)
		}
		asts = append(asts, ast)
	}

	lexast := asts[len(asts)-1]
	for i := len(asts) - 2; i >= 0; i-- {
		lexast = frontend.NewAltMatch(asts[i], lexast)
	}

	program, err := frontend.Generate(lexast)
	if err != nil {
		log.Fatal(err)
	}

	for i, inst := range program {
		fmt.Printf("%3d %s\n", i, inst.Serialize())
	}
}
Ejemplo n.º 2
0
// Compiles the supplied patterns. You don't need
func (self *Lexer) Compile() error {
	if len(self.patterns) == 0 {
		return fmt.Errorf("No patterns added")
	}

	asts := make([]frontend.AST, 0, len(self.patterns))
	for _, p := range self.patterns {
		ast, err := frontend.Parse(p.regex)
		if err != nil {
			return err
		}
		asts = append(asts, ast)
	}

	lexast := asts[len(asts)-1]
	for i := len(asts) - 2; i >= 0; i-- {
		lexast = frontend.NewAltMatch(asts[i], lexast)
	}

	program, err := frontend.Generate(lexast)
	if err != nil {
		return err
	}

	self.program = program
	self.matches = make(map[int]int)

	ast := 0
	for i, instruction := range self.program {
		if instruction.Op == inst.MATCH {
			self.matches[i] = ast
			ast += 1
		}
	}

	if len(asts) != ast {
		panic("len(asts) != ast")
	}

	return nil
}