golang example_test 代码
文件路径：/src/go/scanner/example_test.go
/ Copyright 2012 The Go Authors. All rights reserved.
/ Use of this source code is governed by a BSD-style
/ license that can be found in the LICENSE file.
package scanner_test
import (
"fmt"
"go/scanner"
"go/token"
)
func ExampleScanner_Scan() {
/ src is the input that we want to tokenize.
src := []byte("cos(x) + 1i*sin(x) / Euler")
/ Initialize the scanner.
var s scanner.Scanner
fset := token.NewFileSet() / positions are relative to fset
file := fset.AddFile("", fset.Base(), len(src)) / register input "file"
s.Init(file, src, nil /* no error handler */, scanner.ScanComments)
/ Repeated calls to Scan yield the token sequence found in the input.
for {
pos, tok, lit := s.Scan()
if tok == token.EOF {
break
}
fmt.Printf("%s\t%s\t%q\n", fset.Position(pos), tok, lit)
}
/ output:
/ 1:1 IDENT "cos"
/ 1:4 ( ""
/ 1:5 IDENT "x"
/ 1:6 ) ""
/ 1:8 + ""
/ 1:10 IMAG "1i"
/ 1:12 * ""
/ 1:13 IDENT "sin"
/ 1:16 ( ""
/ 1:17 IDENT "x"
/ 1:18 ) ""
/ 1:20 ; "\n"
/ 1:20 COMMENT "/ Euler"
}