main.go

package main

import (
	"flag"
	"fmt"
	"io"
	"os"
	"strings"
)

var (
	flagToken = flag.Bool("t", false, "Show the tokens")
	flagDebug = flag.Bool("d", false, "Show debug information")
)

func main() {
	flag.Parse()
	buf, _ := io.ReadAll(os.Stdin)
	lexer := NewLexer(string(buf))

	tokens := lexer.Lex()

	tree := Parse(tokens)
	if *flagToken {
		for _, token := range tokens {
			fmt.Printf("Type: %v, Subtype: %v, Value: %q\n", token.Type, token.Subtype, token.Value)
		}
	}
	if *flagDebug {
		indent += "+"
	}

	w := New(os.Stdout)
	Pretty(w, tree, 0)

	if *flagDebug {
		structure(tree, 0)
	}
}

func structure(n *Node, depth int) {
	if n.Parent == nil {
		for i := range n.List {
			structure(n.List[i], depth+1)
		}
		return
	}

	fmt.Printf("[%s] List %d token: %q \t\t(parent: %q)\n", strings.Repeat(" ", depth), len(n.List), n.Token.Value, n.Parent.Token.Value)

	for _, n := range n.List {
		structure(n, depth+1)
	}
}