| Class | Description | 
|---|---|
| AbstractMostlySingleton<T> | 
 Base class for arbitrary-size sets that very efficient (more efficient than HashSet) for 0 and 1
 elements. 
 | 
| IdentityMostlySingleton<T> | 
 An arbitrary-size set that is very efficient (more efficient than HashSet) for 0 and 1 elements. 
 | 
| MostlySingleton<T> | 
 A set that is more efficient than HashSet for 0 and 1 elements. 
 | 
| NodeUtils | 
 A utility class to operate on a given  
Node. | 
| PurityChecker | 
 A visitor that determines the purity (as defined by  
SideEffectFree, Deterministic, and Pure) of a statement or expression. | 
| PurityChecker.PurityCheckerHelper | 
 Helper class to keep  
PurityChecker's interface clean. | 
| PurityChecker.PurityResult | 
 Result of the  
PurityChecker. | 
| PurityUtils | |
| UnmodifiableIdentityHashMap<K,V> | 
 A wrapper around an  
IdentityHashMap that makes it unmodifiable. | 
| Enum | Description | 
|---|---|
| AbstractMostlySingleton.State | 
 The possible states of this set. 
 |