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57 lines
1.1 KiB
Go
57 lines
1.1 KiB
Go
// Copyright © 2016 Alan A. A. Donovan & Brian W. Kernighan.
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// License: https://creativecommons.org/licenses/by-nc-sa/4.0/
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// See page 214.
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//!+
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// Xmlselect prints the text of selected elements of an XML document.
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package main
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import (
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"encoding/xml"
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"fmt"
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"io"
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"os"
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"strings"
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)
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func main() {
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dec := xml.NewDecoder(os.Stdin)
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var stack []string // stack of element names
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for {
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tok, err := dec.Token()
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if err == io.EOF {
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break
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} else if err != nil {
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fmt.Fprintf(os.Stderr, "xmlselect: %v\n", err)
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os.Exit(1)
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}
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switch tok := tok.(type) {
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case xml.StartElement:
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stack = append(stack, tok.Name.Local) // push
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case xml.EndElement:
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stack = stack[:len(stack)-1] // pop
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case xml.CharData:
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if containsAll(stack, os.Args[1:]) {
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fmt.Printf("%s: %s\n", strings.Join(stack, " "), tok)
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}
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}
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}
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}
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// containsAll reports whether x contains the elements of y, in order.
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func containsAll(x, y []string) bool {
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for len(y) <= len(x) {
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if len(y) == 0 {
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return true
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}
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if x[0] == y[0] {
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y = y[1:]
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}
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x = x[1:]
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}
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return false
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}
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//!-
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