Index: 2014/go4gophers/organs3.go |
=================================================================== |
new file mode 100644 |
--- /dev/null |
+++ b/2014/go4gophers/organs3.go |
@@ -0,0 +1,65 @@ |
+package main |
+ |
+import ( |
+ "fmt" |
+ "sort" |
+) |
+ |
+type Organ struct { |
+ Name string |
+ Weight Grams |
+} |
+ |
+func (o *Organ) String() string { return fmt.Sprintf("%v (%v)", o.Name, o.Weight) } |
+ |
+type Grams int |
+ |
+func (g Grams) String() string { return fmt.Sprintf("%dg", int(g)) } |
+ |
+type Organs []*Organ |
+ |
+func (s Organs) Len() int { return len(s) } |
+func (s Organs) Swap(i, j int) { s[i], s[j] = s[j], s[i] } |
+ |
+type ByName struct{ Organs } |
+ |
+func (s ByName) Less(i, j int) bool { return s.Organs[i].Name < s.Organs[j].Name } |
+ |
+type ByWeight struct{ Organs } |
+ |
+func (s ByWeight) Less(i, j int) bool { return s.Organs[i].Weight < s.Organs[j].Weight } |
+ |
+func main() { |
+ s := []*Organ{ |
+ {"brain", 1340}, |
+ {"heart", 290}, |
+ {"liver", 1494}, |
+ {"pancreas", 131}, |
+ {"spleen", 162}, |
+ } |
+ |
+ // START OMIT |
+ sort.Sort(Reverse(ByWeight{s})) // HL |
+ printOrgans("Organs by weight (descending)", s) |
+ |
+ sort.Sort(Reverse(ByName{s})) // HL |
+ printOrgans("Organs by name (descending)", s) |
+ // STOP OMIT |
+} |
+ |
+func printOrgans(t string, s []*Organ) { |
+ fmt.Printf("%s:\n", t) |
+ for _, o := range s { |
+ fmt.Printf(" %v\n", o) |
+ } |
+} |
+ |
+func Reverse(data sort.Interface) sort.Interface { |
+ return &reverse{data} |
+} |
+ |
+type reverse struct{ sort.Interface } |
+ |
+func (r reverse) Less(i, j int) bool { |
+ return r.Interface.Less(j, i) // HL |
+} |