diff options
Diffstat (limited to 'vendor/github.com/hashicorp/terraform/dag/set.go')
-rw-r--r-- | vendor/github.com/hashicorp/terraform/dag/set.go | 109 |
1 files changed, 109 insertions, 0 deletions
diff --git a/vendor/github.com/hashicorp/terraform/dag/set.go b/vendor/github.com/hashicorp/terraform/dag/set.go new file mode 100644 index 0000000..3929c9d --- /dev/null +++ b/vendor/github.com/hashicorp/terraform/dag/set.go | |||
@@ -0,0 +1,109 @@ | |||
1 | package dag | ||
2 | |||
3 | import ( | ||
4 | "sync" | ||
5 | ) | ||
6 | |||
7 | // Set is a set data structure. | ||
8 | type Set struct { | ||
9 | m map[interface{}]interface{} | ||
10 | once sync.Once | ||
11 | } | ||
12 | |||
13 | // Hashable is the interface used by set to get the hash code of a value. | ||
14 | // If this isn't given, then the value of the item being added to the set | ||
15 | // itself is used as the comparison value. | ||
16 | type Hashable interface { | ||
17 | Hashcode() interface{} | ||
18 | } | ||
19 | |||
20 | // hashcode returns the hashcode used for set elements. | ||
21 | func hashcode(v interface{}) interface{} { | ||
22 | if h, ok := v.(Hashable); ok { | ||
23 | return h.Hashcode() | ||
24 | } | ||
25 | |||
26 | return v | ||
27 | } | ||
28 | |||
29 | // Add adds an item to the set | ||
30 | func (s *Set) Add(v interface{}) { | ||
31 | s.once.Do(s.init) | ||
32 | s.m[hashcode(v)] = v | ||
33 | } | ||
34 | |||
35 | // Delete removes an item from the set. | ||
36 | func (s *Set) Delete(v interface{}) { | ||
37 | s.once.Do(s.init) | ||
38 | delete(s.m, hashcode(v)) | ||
39 | } | ||
40 | |||
41 | // Include returns true/false of whether a value is in the set. | ||
42 | func (s *Set) Include(v interface{}) bool { | ||
43 | s.once.Do(s.init) | ||
44 | _, ok := s.m[hashcode(v)] | ||
45 | return ok | ||
46 | } | ||
47 | |||
48 | // Intersection computes the set intersection with other. | ||
49 | func (s *Set) Intersection(other *Set) *Set { | ||
50 | result := new(Set) | ||
51 | if s == nil { | ||
52 | return result | ||
53 | } | ||
54 | if other != nil { | ||
55 | for _, v := range s.m { | ||
56 | if other.Include(v) { | ||
57 | result.Add(v) | ||
58 | } | ||
59 | } | ||
60 | } | ||
61 | |||
62 | return result | ||
63 | } | ||
64 | |||
65 | // Difference returns a set with the elements that s has but | ||
66 | // other doesn't. | ||
67 | func (s *Set) Difference(other *Set) *Set { | ||
68 | result := new(Set) | ||
69 | if s != nil { | ||
70 | for k, v := range s.m { | ||
71 | var ok bool | ||
72 | if other != nil { | ||
73 | _, ok = other.m[k] | ||
74 | } | ||
75 | if !ok { | ||
76 | result.Add(v) | ||
77 | } | ||
78 | } | ||
79 | } | ||
80 | |||
81 | return result | ||
82 | } | ||
83 | |||
84 | // Len is the number of items in the set. | ||
85 | func (s *Set) Len() int { | ||
86 | if s == nil { | ||
87 | return 0 | ||
88 | } | ||
89 | |||
90 | return len(s.m) | ||
91 | } | ||
92 | |||
93 | // List returns the list of set elements. | ||
94 | func (s *Set) List() []interface{} { | ||
95 | if s == nil { | ||
96 | return nil | ||
97 | } | ||
98 | |||
99 | r := make([]interface{}, 0, len(s.m)) | ||
100 | for _, v := range s.m { | ||
101 | r = append(r, v) | ||
102 | } | ||
103 | |||
104 | return r | ||
105 | } | ||
106 | |||
107 | func (s *Set) init() { | ||
108 | s.m = make(map[interface{}]interface{}) | ||
109 | } | ||