github.com/ltltlt/go-source-code@v0.0.0-20190830023027-95be009773aa/strings/example_test.go (about)

     1  // Copyright 2012 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  package strings_test
     6  
     7  import (
     8  	"fmt"
     9  	"strings"
    10  	"unicode"
    11  )
    12  
    13  func ExampleFields() {
    14  	fmt.Printf("Fields are: %q", strings.Fields("  foo bar  baz   "))
    15  	// Output: Fields are: ["foo" "bar" "baz"]
    16  }
    17  
    18  func ExampleFieldsFunc() {
    19  	f := func(c rune) bool {
    20  		return !unicode.IsLetter(c) && !unicode.IsNumber(c)
    21  	}
    22  	fmt.Printf("Fields are: %q", strings.FieldsFunc("  foo1;bar2,baz3...", f))
    23  	// Output: Fields are: ["foo1" "bar2" "baz3"]
    24  }
    25  
    26  func ExampleCompare() {
    27  	fmt.Println(strings.Compare("a", "b"))
    28  	fmt.Println(strings.Compare("a", "a"))
    29  	fmt.Println(strings.Compare("b", "a"))
    30  	// Output:
    31  	// -1
    32  	// 0
    33  	// 1
    34  }
    35  
    36  func ExampleContains() {
    37  	fmt.Println(strings.Contains("seafood", "foo"))
    38  	fmt.Println(strings.Contains("seafood", "bar"))
    39  	fmt.Println(strings.Contains("seafood", ""))
    40  	fmt.Println(strings.Contains("", ""))
    41  	// Output:
    42  	// true
    43  	// false
    44  	// true
    45  	// true
    46  }
    47  
    48  func ExampleContainsAny() {
    49  	fmt.Println(strings.ContainsAny("team", "i"))
    50  	fmt.Println(strings.ContainsAny("failure", "u & i"))
    51  	fmt.Println(strings.ContainsAny("foo", ""))
    52  	fmt.Println(strings.ContainsAny("", ""))
    53  	// Output:
    54  	// false
    55  	// true
    56  	// false
    57  	// false
    58  }
    59  
    60  func ExampleContainsRune() {
    61  	// Finds whether a string contains a particular Unicode code point.
    62  	// The code point for the lowercase letter "a", for example, is 97.
    63  	fmt.Println(strings.ContainsRune("aardvark", 97))
    64  	fmt.Println(strings.ContainsRune("timeout", 97))
    65  	// Output:
    66  	// true
    67  	// false
    68  }
    69  
    70  func ExampleCount() {
    71  	fmt.Println(strings.Count("cheese", "e"))
    72  	fmt.Println(strings.Count("five", "")) // before & after each rune
    73  	// Output:
    74  	// 3
    75  	// 5
    76  }
    77  
    78  func ExampleEqualFold() {
    79  	fmt.Println(strings.EqualFold("Go", "go"))
    80  	// Output: true
    81  }
    82  
    83  func ExampleHasPrefix() {
    84  	fmt.Println(strings.HasPrefix("Gopher", "Go"))
    85  	fmt.Println(strings.HasPrefix("Gopher", "C"))
    86  	fmt.Println(strings.HasPrefix("Gopher", ""))
    87  	// Output:
    88  	// true
    89  	// false
    90  	// true
    91  }
    92  
    93  func ExampleHasSuffix() {
    94  	fmt.Println(strings.HasSuffix("Amigo", "go"))
    95  	fmt.Println(strings.HasSuffix("Amigo", "O"))
    96  	fmt.Println(strings.HasSuffix("Amigo", "Ami"))
    97  	fmt.Println(strings.HasSuffix("Amigo", ""))
    98  	// Output:
    99  	// true
   100  	// false
   101  	// false
   102  	// true
   103  }
   104  
   105  func ExampleIndex() {
   106  	fmt.Println(strings.Index("chicken", "ken"))
   107  	fmt.Println(strings.Index("chicken", "dmr"))
   108  	// Output:
   109  	// 4
   110  	// -1
   111  }
   112  
   113  func ExampleIndexFunc() {
   114  	f := func(c rune) bool {
   115  		return unicode.Is(unicode.Han, c)
   116  	}
   117  	fmt.Println(strings.IndexFunc("Hello, 世界", f))
   118  	fmt.Println(strings.IndexFunc("Hello, world", f))
   119  	// Output:
   120  	// 7
   121  	// -1
   122  }
   123  
   124  func ExampleIndexAny() {
   125  	fmt.Println(strings.IndexAny("chicken", "aeiouy"))
   126  	fmt.Println(strings.IndexAny("crwth", "aeiouy"))
   127  	// Output:
   128  	// 2
   129  	// -1
   130  }
   131  
   132  func ExampleIndexByte() {
   133  	fmt.Println(strings.IndexByte("golang", 'g'))
   134  	fmt.Println(strings.IndexByte("gophers", 'h'))
   135  	fmt.Println(strings.IndexByte("golang", 'x'))
   136  	// Output:
   137  	// 0
   138  	// 3
   139  	// -1
   140  }
   141  func ExampleIndexRune() {
   142  	fmt.Println(strings.IndexRune("chicken", 'k'))
   143  	fmt.Println(strings.IndexRune("chicken", 'd'))
   144  	// Output:
   145  	// 4
   146  	// -1
   147  }
   148  
   149  func ExampleLastIndex() {
   150  	fmt.Println(strings.Index("go gopher", "go"))
   151  	fmt.Println(strings.LastIndex("go gopher", "go"))
   152  	fmt.Println(strings.LastIndex("go gopher", "rodent"))
   153  	// Output:
   154  	// 0
   155  	// 3
   156  	// -1
   157  }
   158  
   159  func ExampleLastIndexAny() {
   160  	fmt.Println(strings.LastIndexAny("go gopher", "go"))
   161  	fmt.Println(strings.LastIndexAny("go gopher", "rodent"))
   162  	fmt.Println(strings.LastIndexAny("go gopher", "fail"))
   163  	// Output:
   164  	// 4
   165  	// 8
   166  	// -1
   167  }
   168  
   169  func ExampleLastIndexByte() {
   170  	fmt.Println(strings.LastIndexByte("Hello, world", 'l'))
   171  	fmt.Println(strings.LastIndexByte("Hello, world", 'o'))
   172  	fmt.Println(strings.LastIndexByte("Hello, world", 'x'))
   173  	// Output:
   174  	// 10
   175  	// 8
   176  	// -1
   177  }
   178  
   179  func ExampleLastIndexFunc() {
   180  	fmt.Println(strings.LastIndexFunc("go 123", unicode.IsNumber))
   181  	fmt.Println(strings.LastIndexFunc("123 go", unicode.IsNumber))
   182  	fmt.Println(strings.LastIndexFunc("go", unicode.IsNumber))
   183  	// Output:
   184  	// 5
   185  	// 2
   186  	// -1
   187  }
   188  
   189  func ExampleJoin() {
   190  	s := []string{"foo", "bar", "baz"}
   191  	fmt.Println(strings.Join(s, ", "))
   192  	// Output: foo, bar, baz
   193  }
   194  
   195  func ExampleRepeat() {
   196  	fmt.Println("ba" + strings.Repeat("na", 2))
   197  	// Output: banana
   198  }
   199  
   200  func ExampleReplace() {
   201  	fmt.Println(strings.Replace("oink oink oink", "k", "ky", 2))
   202  	fmt.Println(strings.Replace("oink oink oink", "oink", "moo", -1))
   203  	// Output:
   204  	// oinky oinky oink
   205  	// moo moo moo
   206  }
   207  
   208  func ExampleSplit() {
   209  	fmt.Printf("%q\n", strings.Split("a,b,c", ","))
   210  	fmt.Printf("%q\n", strings.Split("a man a plan a canal panama", "a "))
   211  	fmt.Printf("%q\n", strings.Split(" xyz ", ""))
   212  	fmt.Printf("%q\n", strings.Split("", "Bernardo O'Higgins"))
   213  	// Output:
   214  	// ["a" "b" "c"]
   215  	// ["" "man " "plan " "canal panama"]
   216  	// [" " "x" "y" "z" " "]
   217  	// [""]
   218  }
   219  
   220  func ExampleSplitN() {
   221  	fmt.Printf("%q\n", strings.SplitN("a,b,c", ",", 2))
   222  	z := strings.SplitN("a,b,c", ",", 0)
   223  	fmt.Printf("%q (nil = %v)\n", z, z == nil)
   224  	// Output:
   225  	// ["a" "b,c"]
   226  	// [] (nil = true)
   227  }
   228  
   229  func ExampleSplitAfter() {
   230  	fmt.Printf("%q\n", strings.SplitAfter("a,b,c", ","))
   231  	// Output: ["a," "b," "c"]
   232  }
   233  
   234  func ExampleSplitAfterN() {
   235  	fmt.Printf("%q\n", strings.SplitAfterN("a,b,c", ",", 2))
   236  	// Output: ["a," "b,c"]
   237  }
   238  
   239  func ExampleTitle() {
   240  	fmt.Println(strings.Title("her royal highness"))
   241  	// Output: Her Royal Highness
   242  }
   243  
   244  func ExampleToTitle() {
   245  	fmt.Println(strings.ToTitle("loud noises"))
   246  	fmt.Println(strings.ToTitle("хлеб"))
   247  	// Output:
   248  	// LOUD NOISES
   249  	// ХЛЕБ
   250  }
   251  
   252  func ExampleToTitleSpecial() {
   253  	fmt.Println(strings.ToTitleSpecial(unicode.TurkishCase, "dünyanın ilk borsa yapısı Aizonai kabul edilir"))
   254  	// Output:
   255  	// DÜNYANIN İLK BORSA YAPISI AİZONAİ KABUL EDİLİR
   256  }
   257  
   258  func ExampleMap() {
   259  	rot13 := func(r rune) rune {
   260  		switch {
   261  		case r >= 'A' && r <= 'Z':
   262  			return 'A' + (r-'A'+13)%26
   263  		case r >= 'a' && r <= 'z':
   264  			return 'a' + (r-'a'+13)%26
   265  		}
   266  		return r
   267  	}
   268  	fmt.Println(strings.Map(rot13, "'Twas brillig and the slithy gopher..."))
   269  	// Output: 'Gjnf oevyyvt naq gur fyvgul tbcure...
   270  }
   271  
   272  func ExampleNewReplacer() {
   273  	r := strings.NewReplacer("<", "&lt;", ">", "&gt;")
   274  	fmt.Println(r.Replace("This is <b>HTML</b>!"))
   275  	// Output: This is &lt;b&gt;HTML&lt;/b&gt;!
   276  }
   277  
   278  func ExampleToUpper() {
   279  	fmt.Println(strings.ToUpper("Gopher"))
   280  	// Output: GOPHER
   281  }
   282  
   283  func ExampleToUpperSpecial() {
   284  	fmt.Println(strings.ToUpperSpecial(unicode.TurkishCase, "örnek iş"))
   285  	// Output: ÖRNEK İŞ
   286  }
   287  
   288  func ExampleToLower() {
   289  	fmt.Println(strings.ToLower("Gopher"))
   290  	// Output: gopher
   291  }
   292  
   293  func ExampleToLowerSpecial() {
   294  	fmt.Println(strings.ToLowerSpecial(unicode.TurkishCase, "Önnek İş"))
   295  	// Output: önnek iş
   296  }
   297  
   298  func ExampleTrim() {
   299  	fmt.Print(strings.Trim("¡¡¡Hello, Gophers!!!", "!¡"))
   300  	// Output: Hello, Gophers
   301  }
   302  
   303  func ExampleTrimSpace() {
   304  	fmt.Println(strings.TrimSpace(" \t\n Hello, Gophers \n\t\r\n"))
   305  	// Output: Hello, Gophers
   306  }
   307  
   308  func ExampleTrimPrefix() {
   309  	var s = "¡¡¡Hello, Gophers!!!"
   310  	s = strings.TrimPrefix(s, "¡¡¡Hello, ")
   311  	s = strings.TrimPrefix(s, "¡¡¡Howdy, ")
   312  	fmt.Print(s)
   313  	// Output: Gophers!!!
   314  }
   315  
   316  func ExampleTrimSuffix() {
   317  	var s = "¡¡¡Hello, Gophers!!!"
   318  	s = strings.TrimSuffix(s, ", Gophers!!!")
   319  	s = strings.TrimSuffix(s, ", Marmots!!!")
   320  	fmt.Print(s)
   321  	// Output: ¡¡¡Hello
   322  }
   323  
   324  func ExampleTrimFunc() {
   325  	fmt.Print(strings.TrimFunc("¡¡¡Hello, Gophers!!!", func(r rune) bool {
   326  		return !unicode.IsLetter(r) && !unicode.IsNumber(r)
   327  	}))
   328  	// Output: Hello, Gophers
   329  }
   330  
   331  func ExampleTrimLeft() {
   332  	fmt.Print(strings.TrimLeft("¡¡¡Hello, Gophers!!!", "!¡"))
   333  	// Output: Hello, Gophers!!!
   334  }
   335  
   336  func ExampleTrimLeftFunc() {
   337  	fmt.Print(strings.TrimLeftFunc("¡¡¡Hello, Gophers!!!", func(r rune) bool {
   338  		return !unicode.IsLetter(r) && !unicode.IsNumber(r)
   339  	}))
   340  	// Output: Hello, Gophers!!!
   341  }
   342  
   343  func ExampleTrimRight() {
   344  	fmt.Print(strings.TrimRight("¡¡¡Hello, Gophers!!!", "!¡"))
   345  	// Output: ¡¡¡Hello, Gophers
   346  }
   347  
   348  func ExampleTrimRightFunc() {
   349  	fmt.Print(strings.TrimRightFunc("¡¡¡Hello, Gophers!!!", func(r rune) bool {
   350  		return !unicode.IsLetter(r) && !unicode.IsNumber(r)
   351  	}))
   352  	// Output: ¡¡¡Hello, Gophers
   353  }
   354  
   355  func ExampleBuilder() {
   356  	var b strings.Builder
   357  	for i := 3; i >= 1; i-- {
   358  		fmt.Fprintf(&b, "%d...", i)
   359  	}
   360  	b.WriteString("ignition")
   361  	fmt.Println(b.String())
   362  
   363  	// Output: 3...2...1...ignition
   364  }