1. Dart
2. dart:svg
3. AttributeClassSet
4. lookup method

##### AttributeClassSet class

1. Constructors
2. AttributeClassSet
3. Properties
4. first
5. frozen
6. hashCode
7. isEmpty
8. isNotEmpty
9. iterator
10. last
11. length
12. runtimeType
13. single
14. Methods
15. readClasses
16. writeClasses
17. add
18. addAll
19. any
20. cast
21. clear
22. contains
23. containsAll
24. difference
25. elementAt
26. every
27. expand
28. firstWhere
29. fold
30. followedBy
31. forEach
32. intersection
33. join
34. lastWhere
35. lookup
36. map
37. modify
38. noSuchMethod
39. reduce
40. remove
41. removeAll
42. removeWhere
43. retainAll
44. retainWhere
45. singleWhere
46. skip
47. skipWhile
48. take
49. takeWhile
50. toggle
51. toggleAll
52. toList
53. toSet
54. toString
55. union
56. where
57. whereType
58. Operators
59. operator ==

# lookup method

String lookup (Object value)
inherited

Lookup from the Set interface. Not interesting for a String set.

## Implementation

    String lookup(Object value) => contains(value) ? value : null;