1 // Copyright 2011 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 sort_test 6 7 import ( 8 "fmt" 9 "sort" 10 ) 11 12 type Grams int 13 14 func (g Grams) String() string { return fmt.Sprintf("%dg", int(g)) } 15 16 type Organ struct { 17 Name string 18 Weight Grams 19 } 20 21 type Organs []*Organ 22 23 func (s Organs) Len() int { return len(s) } 24 func (s Organs) Swap(i, j int) { s[i], s[j] = s[j], s[i] } 25 26 // ByName implements sort.Interface by providing Less and using the Len and 27 // Swap methods of the embedded Organs value. 28 type ByName struct{ Organs } 29 30 func (s ByName) Less(i, j int) bool { return s.Organs[i].Name < s.Organs[j].Name } 31 32 // ByWeight implements sort.Interface by providing Less and using the Len and 33 // Swap methods of the embedded Organs value. 34 type ByWeight struct{ Organs } 35 36 func (s ByWeight) Less(i, j int) bool { return s.Organs[i].Weight < s.Organs[j].Weight } 37 38 func Example_sortWrapper() { 39 s := []*Organ{ 40 {"brain", 1340}, 41 {"heart", 290}, 42 {"liver", 1494}, 43 {"pancreas", 131}, 44 {"prostate", 62}, 45 {"spleen", 162}, 46 } 47 48 sort.Sort(ByWeight{s}) 49 fmt.Println("Organs by weight:") 50 printOrgans(s) 51 52 sort.Sort(ByName{s}) 53 fmt.Println("Organs by name:") 54 printOrgans(s) 55 56 // Output: 57 // Organs by weight: 58 // prostate (62g) 59 // pancreas (131g) 60 // spleen (162g) 61 // heart (290g) 62 // brain (1340g) 63 // liver (1494g) 64 // Organs by name: 65 // brain (1340g) 66 // heart (290g) 67 // liver (1494g) 68 // pancreas (131g) 69 // prostate (62g) 70 // spleen (162g) 71 } 72 73 func printOrgans(s []*Organ) { 74 for _, o := range s { 75 fmt.Printf("%-8s (%v)\n", o.Name, o.Weight) 76 } 77 } 78
