github.com/geraldss/go/src@v0.0.0-20210511222824-ac7d0ebfc235/container/ring/example_test.go (about)

     1  // Copyright 2017 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 ring_test
     6  
     7  import (
     8  	"container/ring"
     9  	"fmt"
    10  )
    11  
    12  func ExampleRing_Len() {
    13  	// Create a new ring of size 4
    14  	r := ring.New(4)
    15  
    16  	// Print out its length
    17  	fmt.Println(r.Len())
    18  
    19  	// Output:
    20  	// 4
    21  }
    22  
    23  func ExampleRing_Next() {
    24  	// Create a new ring of size 5
    25  	r := ring.New(5)
    26  
    27  	// Get the length of the ring
    28  	n := r.Len()
    29  
    30  	// Initialize the ring with some integer values
    31  	for i := 0; i < n; i++ {
    32  		r.Value = i
    33  		r = r.Next()
    34  	}
    35  
    36  	// Iterate through the ring and print its contents
    37  	for j := 0; j < n; j++ {
    38  		fmt.Println(r.Value)
    39  		r = r.Next()
    40  	}
    41  
    42  	// Output:
    43  	// 0
    44  	// 1
    45  	// 2
    46  	// 3
    47  	// 4
    48  }
    49  
    50  func ExampleRing_Prev() {
    51  	// Create a new ring of size 5
    52  	r := ring.New(5)
    53  
    54  	// Get the length of the ring
    55  	n := r.Len()
    56  
    57  	// Initialize the ring with some integer values
    58  	for i := 0; i < n; i++ {
    59  		r.Value = i
    60  		r = r.Next()
    61  	}
    62  
    63  	// Iterate through the ring backwards and print its contents
    64  	for j := 0; j < n; j++ {
    65  		r = r.Prev()
    66  		fmt.Println(r.Value)
    67  	}
    68  
    69  	// Output:
    70  	// 4
    71  	// 3
    72  	// 2
    73  	// 1
    74  	// 0
    75  }
    76  
    77  func ExampleRing_Do() {
    78  	// Create a new ring of size 5
    79  	r := ring.New(5)
    80  
    81  	// Get the length of the ring
    82  	n := r.Len()
    83  
    84  	// Initialize the ring with some integer values
    85  	for i := 0; i < n; i++ {
    86  		r.Value = i
    87  		r = r.Next()
    88  	}
    89  
    90  	// Iterate through the ring and print its contents
    91  	r.Do(func(p interface{}) {
    92  		fmt.Println(p.(int))
    93  	})
    94  
    95  	// Output:
    96  	// 0
    97  	// 1
    98  	// 2
    99  	// 3
   100  	// 4
   101  }
   102  
   103  func ExampleRing_Move() {
   104  	// Create a new ring of size 5
   105  	r := ring.New(5)
   106  
   107  	// Get the length of the ring
   108  	n := r.Len()
   109  
   110  	// Initialize the ring with some integer values
   111  	for i := 0; i < n; i++ {
   112  		r.Value = i
   113  		r = r.Next()
   114  	}
   115  
   116  	// Move the pointer forward by three steps
   117  	r = r.Move(3)
   118  
   119  	// Iterate through the ring and print its contents
   120  	r.Do(func(p interface{}) {
   121  		fmt.Println(p.(int))
   122  	})
   123  
   124  	// Output:
   125  	// 3
   126  	// 4
   127  	// 0
   128  	// 1
   129  	// 2
   130  }
   131  
   132  func ExampleRing_Link() {
   133  	// Create two rings, r and s, of size 2
   134  	r := ring.New(2)
   135  	s := ring.New(2)
   136  
   137  	// Get the length of the ring
   138  	lr := r.Len()
   139  	ls := s.Len()
   140  
   141  	// Initialize r with 0s
   142  	for i := 0; i < lr; i++ {
   143  		r.Value = 0
   144  		r = r.Next()
   145  	}
   146  
   147  	// Initialize s with 1s
   148  	for j := 0; j < ls; j++ {
   149  		s.Value = 1
   150  		s = s.Next()
   151  	}
   152  
   153  	// Link ring r and ring s
   154  	rs := r.Link(s)
   155  
   156  	// Iterate through the combined ring and print its contents
   157  	rs.Do(func(p interface{}) {
   158  		fmt.Println(p.(int))
   159  	})
   160  
   161  	// Output:
   162  	// 0
   163  	// 0
   164  	// 1
   165  	// 1
   166  }
   167  
   168  func ExampleRing_Unlink() {
   169  	// Create a new ring of size 6
   170  	r := ring.New(6)
   171  
   172  	// Get the length of the ring
   173  	n := r.Len()
   174  
   175  	// Initialize the ring with some integer values
   176  	for i := 0; i < n; i++ {
   177  		r.Value = i
   178  		r = r.Next()
   179  	}
   180  
   181  	// Unlink three elements from r, starting from r.Next()
   182  	r.Unlink(3)
   183  
   184  	// Iterate through the remaining ring and print its contents
   185  	r.Do(func(p interface{}) {
   186  		fmt.Println(p.(int))
   187  	})
   188  
   189  	// Output:
   190  	// 0
   191  	// 4
   192  	// 5
   193  }