add set data structure

src/datastruct/set/set.go

@@ -0,0 +1,122 @@
+package set
+
+import "github.com/HDT3213/godis/src/datastruct/dict"
+
+type Set struct {
+    dict *dict.Dict
+}
+
+func Make(shardCountHint int)*Set {
+    return &Set{
+        dict: dict.Make(shardCountHint),
+    }
+}
+
+func MakeFromVals(members ...string)*Set {
+    set := &Set{
+        dict: dict.Make(len(members)),
+    }
+    for _, member := range members {
+        set.Add(member)
+    }
+    return set
+}
+
+func (set *Set)Add(val string)int {
+    return set.dict.Put(val, true)
+}
+
+func (set *Set)Remove(val string)int {
+    return set.dict.Remove(val)
+}
+
+func (set *Set)Has(val string)bool {
+    _, exists := set.dict.Get(val)
+    return exists
+}
+
+func (set *Set)Len()int {
+    return set.dict.Len()
+}
+
+func (set *Set)ToSlice()[]string {
+    slice := make([]string, set.Len())
+    i := 0
+    set.dict.ForEach(func(key string, val interface{})bool {
+        if i < len(slice) {
+           slice[i] = key
+        } else {
+            // set extended during traversal
+            slice = append(slice, key)
+        }
+        i++
+        return true
+    })
+    return slice
+}
+
+func (set *Set)ForEach(consumer func(member string)bool) {
+    set.dict.ForEach(func(key string, val interface{})bool {
+        return consumer(key)
+    })
+}
+
+func (set *Set)Intersect(another *Set)*Set {
+    if set == nil {
+        panic("set is nil")
+    }
+    setSize := set.Len()
+    anotherSize := another.Len()
+    size := setSize
+    if anotherSize < setSize {
+        size = anotherSize
+    }
+
+    result := Make(size)
+    another.ForEach(func(member string)bool {
+        if set.Has(member) {
+            result.Add(member)
+        }
+        return true
+    })
+    return result
+}
+
+func (set *Set)Union(another *Set)*Set {
+    if set == nil {
+        panic("set is nil")
+    }
+    result := Make(set.Len() + another.Len())
+    another.ForEach(func(member string)bool {
+        result.Add(member)
+        return true
+    })
+    set.ForEach(func(member string)bool {
+        result.Add(member)
+        return true
+    })
+    return result
+}
+
+func (set *Set)Diff(another *Set)*Set {
+    if set == nil {
+        panic("set is nil")
+    }
+
+    result := Make(set.Len())
+    set.ForEach(func(member string)bool {
+        if !another.Has(member) {
+            result.Add(member)
+        }
+        return true
+    })
+    return result
+}
+
+func (set *Set)RandomMembers(limit int)[]string {
+    return set.dict.RandomKeys(limit)
+}
+
+func (set *Set)RandomDistinctMembers(limit int)[]string {
+    return set.dict.RandomDistinctKeys(limit)
+}