ATNConfigSet

Specialized {@link Set}{@code <}{@link ATNConfig}{@code >} that can track info about the set, with support for combining similar configurations using a graph-structured stack.

The reason that we need this is because we don't want the hash map to use the standard hash code and equals. We need all configurations with the same {@code (s,i,_,semctx)} to be equal. Unfortunately, this key effectively doubles the number of objects associated with ATNConfigs. The other solution is to use a hash table that lets us specify the equals/hashcode operation.

class ATNConfigSet {

class ConfigHashSet;

class ConfigEqualityComparator;

bool readonly_;

AbstractConfigHashSet configLookup;

ATNConfig[] configs;

int uniqueAlt;

BitSet conflictingAlts;

bool hasSemanticContext;

bool dipsIntoOuterContext;

bool fullCtx;

this(bool fullCtx);

this();

this(ATNConfigSet old);

bool add(ATNConfig config);

bool add(ATNConfig config, DoubleKeyMap!(PredictionContext, PredictionContext, PredictionContext) mergeCache);

ATNConfig[] elements();

ATNState[] getStates();

BitSet getAlts();

SemanticContext[] getPredicates();

ATNConfig get(int i);

void optimizeConfigs(InterfaceATNSimulator interpreter);

bool addAll(ATNConfig[] coll);

bool opEquals(Object o);

static bool equals(Object aObj, Object bObj);

size_t toHash();

int size();

bool isEmpty();

bool contains(ATNConfig o);

bool containsFast(ATNConfig obj);

void clear();

void readonly(bool readonly);

string toString();

bool readonly();

}

Constructors

this this(bool fullCtx): Undocumented in source.
this this(): Undocumented in source.
this this(ATNConfigSet old): Undocumented in source.

Members

Classes

ConfigEqualityComparator class ConfigEqualityComparator: TODO add class description
ConfigHashSet class ConfigHashSet: The reason that we need this is because we don't want the hash map to use the standard hash code and equals. We need all configurations with the same {@code (s,i,_,semctx)} to be equal. Unfortunately, this key effectively doubles the number of objects associated with ATNConfigs. The other solution is to use a hash table that lets us specify the equals/hashcode operation.

Functions

add bool add(ATNConfig config): Undocumented in source. Be warned that the author may not have intended to support it.
add bool add(ATNConfig config, DoubleKeyMap!(PredictionContext, PredictionContext, PredictionContext) mergeCache): Adding a new config means merging contexts with existing configs for {@code (s, i, pi, _)}, where {@code s} is the {@link ATNConfig#state}, {@code i} is the {@link ATNConfig#alt}, and {@code pi} is the {@link ATNConfig#semanticContext}. We use {@code (s,i,pi)} as key.
addAll bool addAll(ATNConfig[] coll): Undocumented in source. Be warned that the author may not have intended to support it.
clear void clear(): Undocumented in source. Be warned that the author may not have intended to support it.
contains bool contains(ATNConfig o): Undocumented in source. Be warned that the author may not have intended to support it.
containsFast bool containsFast(ATNConfig obj): Undocumented in source. Be warned that the author may not have intended to support it.
elements ATNConfig[] elements(): @uml Return a List holding list of configs
get ATNConfig get(int i): Undocumented in source. Be warned that the author may not have intended to support it.
getAlts BitSet getAlts(): @uml Gets the complete set of represented alternatives for the configuration set.
getPredicates SemanticContext[] getPredicates(): Undocumented in source. Be warned that the author may not have intended to support it.
getStates ATNState[] getStates(): Undocumented in source. Be warned that the author may not have intended to support it.
isEmpty bool isEmpty(): Undocumented in source. Be warned that the author may not have intended to support it.
opEquals bool opEquals(Object o): @uml @override
optimizeConfigs void optimizeConfigs(InterfaceATNSimulator interpreter): Undocumented in source. Be warned that the author may not have intended to support it.
readonly void readonly(bool readonly): Undocumented in source. Be warned that the author may not have intended to support it.
readonly bool readonly(): Undocumented in source. Be warned that the author may not have intended to support it.
size int size(): Undocumented in source. Be warned that the author may not have intended to support it.
toHash size_t toHash(): @uml @override @safe @nothrow
toString string toString(): @uml @override

Static functions

equals bool equals(Object aObj, Object bObj): Undocumented in source. Be warned that the author may not have intended to support it.

Variables

configLookup AbstractConfigHashSet configLookup;: Undocumented in source.
configs ATNConfig[] configs;: @uml Track the elements as they are added to the set; supports get(i)
conflictingAlts BitSet conflictingAlts;: @uml Currently this is only used when we detect SLL conflict; this does not necessarily represent the ambiguous alternatives. In fact, I should also point out that this seems to include predicated alternatives that have predicates that evaluate to false. Computed in computeTargetState().
dipsIntoOuterContext bool dipsIntoOuterContext;: Undocumented in source.
fullCtx bool fullCtx;: @uml Indicates that this configuration set is part of a full context LL prediction. It will be used to determine how to merge $. With SLL it's a wildcard whereas it is not for LL context merge. @final
hasSemanticContext bool hasSemanticContext;: @uml Used in parser and lexer. In lexer, it indicates we hit a pred while computing a closure operation. Don't make a DFA state from this.
readonly_ bool readonly_;: @uml Indicates that the set of configurations is read-only. Do not allow any code to manipulate the set; DFA states will point at the sets and they must not change. This does not protect the other fields; in particular, conflictingAlts is set after we've made this readonly. @read
uniqueAlt int uniqueAlt;: @uml TODO: these fields make me pretty uncomfortable but nice to pack up info together, saves recomputation TODO: can we track conflicts as they are added to save scanning configs later?