| // 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 COMMENT "// Euler" |
| // 1:28 ; "\n" |
| } |