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package main
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import (
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"bufio"
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"fmt"
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"io"
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"os"
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)
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var DEBUG = false
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func args() {
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filename := os.Args[1]
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f, err := os.Open(filename)
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if err != nil {
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fmt.Fprintln(os.Stderr, "unable to read file ", filename)
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os.Exit(1)
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}
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defer f.Close()
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c := make(chan token, 32)
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go lex(bufio.NewReader(f), c)
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for s := range c {
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fmt.Printf("%11s %s\n", s.t, s.lexeme)
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}
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}
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func main() {
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if len(os.Args) > 1 {
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args()
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return
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}
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r := bufio.NewReader(os.Stdin)
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for {
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fmt.Print("> ")
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line, prefix, err := r.ReadLine()
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if prefix {
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fmt.Println("(prefix)")
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}
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switch err {
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case nil:
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break
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case io.EOF:
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fmt.Print("\n")
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return
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default:
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fmt.Println("error: ", err)
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continue
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}
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c := make(chan token, 32)
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go lexs(string(line)+"\n", c)
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for s := range c {
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fmt.Printf("%11s %s\n", s.t, s.lexeme)
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}
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}
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}
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