antlr4ts
Version:
ANTLR 4 runtime for JavaScript written in Typescript
174 lines • 7.32 kB
JavaScript
"use strict";
/*!
* Copyright 2016 The ANTLR Project. All rights reserved.
* Licensed under the BSD-3-Clause license. See LICENSE file in the project root for license information.
*/
var __decorate = (this && this.__decorate) || function (decorators, target, key, desc) {
var c = arguments.length, r = c < 3 ? target : desc === null ? desc = Object.getOwnPropertyDescriptor(target, key) : desc, d;
if (typeof Reflect === "object" && typeof Reflect.decorate === "function") r = Reflect.decorate(decorators, target, key, desc);
else for (var i = decorators.length - 1; i >= 0; i--) if (d = decorators[i]) r = (c < 3 ? d(r) : c > 3 ? d(target, key, r) : d(target, key)) || r;
return c > 3 && r && Object.defineProperty(target, key, r), r;
};
var __param = (this && this.__param) || function (paramIndex, decorator) {
return function (target, key) { decorator(target, key, paramIndex); }
};
Object.defineProperty(exports, "__esModule", { value: true });
exports.DFA = void 0;
// ConvertTo-TS run at 2016-10-04T11:26:38.3567094-07:00
const Array2DHashSet_1 = require("../misc/Array2DHashSet");
const ATNConfigSet_1 = require("../atn/ATNConfigSet");
const DFASerializer_1 = require("./DFASerializer");
const DFAState_1 = require("./DFAState");
const LexerDFASerializer_1 = require("./LexerDFASerializer");
const Decorators_1 = require("../Decorators");
const ObjectEqualityComparator_1 = require("../misc/ObjectEqualityComparator");
const StarLoopEntryState_1 = require("../atn/StarLoopEntryState");
const VocabularyImpl_1 = require("../VocabularyImpl");
let DFA = class DFA {
constructor(atnStartState, decision = 0) {
/**
* A set of all states in the `DFA`.
*
* Note that this collection of states holds the DFA states for both SLL and LL prediction. Only the start state
* needs to be differentiated for these cases, which is tracked by the `s0` and `s0full` fields.
*/
this.states = new Array2DHashSet_1.Array2DHashSet(ObjectEqualityComparator_1.ObjectEqualityComparator.INSTANCE);
this.nextStateNumber = 0;
if (!atnStartState.atn) {
throw new Error("The ATNState must be associated with an ATN");
}
this.atnStartState = atnStartState;
this.atn = atnStartState.atn;
this.decision = decision;
// Precedence DFAs are associated with the special precedence decision created for left-recursive rules which
// evaluate their alternatives using a precedence hierarchy. When such a decision is encountered, we mark this
// DFA instance as a precedence DFA and initialize the initial states s0 and s0full to special DFAState
// instances which use outgoing edges to link to the actual start state used for each precedence level.
let isPrecedenceDfa = false;
if (atnStartState instanceof StarLoopEntryState_1.StarLoopEntryState) {
if (atnStartState.precedenceRuleDecision) {
isPrecedenceDfa = true;
this.s0 = new DFAState_1.DFAState(new ATNConfigSet_1.ATNConfigSet());
this.s0full = new DFAState_1.DFAState(new ATNConfigSet_1.ATNConfigSet());
}
}
this.precedenceDfa = isPrecedenceDfa;
}
/**
* Gets whether this DFA is a precedence DFA. Precedence DFAs use a special
* start state {@link #s0} which is not stored in {@link #states}. The
* {@link DFAState#edges} array for this start state contains outgoing edges
* supplying individual start states corresponding to specific precedence
* values.
*
* @returns `true` if this is a precedence DFA; otherwise,
* `false`.
* @see Parser.precedence
*/
get isPrecedenceDfa() {
return this.precedenceDfa;
}
/**
* Get the start state for a specific precedence value.
*
* @param precedence The current precedence.
* @returns The start state corresponding to the specified precedence, or
* `undefined` if no start state exists for the specified precedence.
*
* @ if this is not a precedence DFA.
* @see `isPrecedenceDfa`
*/
getPrecedenceStartState(precedence, fullContext) {
if (!this.isPrecedenceDfa) {
throw new Error("Only precedence DFAs may contain a precedence start state.");
}
// s0 and s0full are never null for a precedence DFA
if (fullContext) {
return this.s0full.getTarget(precedence);
}
else {
return this.s0.getTarget(precedence);
}
}
/**
* Set the start state for a specific precedence value.
*
* @param precedence The current precedence.
* @param startState The start state corresponding to the specified
* precedence.
*
* @ if this is not a precedence DFA.
* @see `isPrecedenceDfa`
*/
setPrecedenceStartState(precedence, fullContext, startState) {
if (!this.isPrecedenceDfa) {
throw new Error("Only precedence DFAs may contain a precedence start state.");
}
if (precedence < 0) {
return;
}
if (fullContext) {
// s0full is never null for a precedence DFA
this.s0full.setTarget(precedence, startState);
}
else {
// s0 is never null for a precedence DFA
this.s0.setTarget(precedence, startState);
}
}
get isEmpty() {
if (this.isPrecedenceDfa) {
// s0 and s0full are never null for a precedence DFA
return this.s0.getEdgeMap().size === 0 && this.s0full.getEdgeMap().size === 0;
}
return this.s0 == null && this.s0full == null;
}
get isContextSensitive() {
if (this.isPrecedenceDfa) {
// s0full is never null for a precedence DFA
return this.s0full.getEdgeMap().size > 0;
}
return this.s0full != null;
}
addState(state) {
state.stateNumber = this.nextStateNumber++;
return this.states.getOrAdd(state);
}
toString(vocabulary, ruleNames) {
if (!vocabulary) {
vocabulary = VocabularyImpl_1.VocabularyImpl.EMPTY_VOCABULARY;
}
if (!this.s0) {
return "";
}
let serializer;
if (ruleNames) {
serializer = new DFASerializer_1.DFASerializer(this, vocabulary, ruleNames, this.atnStartState.atn);
}
else {
serializer = new DFASerializer_1.DFASerializer(this, vocabulary);
}
return serializer.toString();
}
toLexerString() {
if (!this.s0) {
return "";
}
let serializer = new LexerDFASerializer_1.LexerDFASerializer(this);
return serializer.toString();
}
};
__decorate([
Decorators_1.NotNull
], DFA.prototype, "states", void 0);
__decorate([
Decorators_1.NotNull
], DFA.prototype, "atnStartState", void 0);
__decorate([
Decorators_1.NotNull
], DFA.prototype, "atn", void 0);
DFA = __decorate([
__param(0, Decorators_1.NotNull)
], DFA);
exports.DFA = DFA;
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