antlr4ts
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ANTLR 4 runtime for JavaScript written in Typescript
160 lines • 7.75 kB
JavaScript
;
/*!
* 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;
};
Object.defineProperty(exports, "__esModule", { value: true });
exports.PredictionMode = void 0;
// ConvertTo-TS run at 2016-10-04T11:26:36.2673893-07:00
const Array2DHashMap_1 = require("../misc/Array2DHashMap");
const MurmurHash_1 = require("../misc/MurmurHash");
const Decorators_1 = require("../Decorators");
const RuleStopState_1 = require("./RuleStopState");
/**
* This enumeration defines the prediction modes available in ANTLR 4 along with
* utility methods for analyzing configuration sets for conflicts and/or
* ambiguities.
*/
var PredictionMode;
(function (PredictionMode) {
/**
* The SLL(*) prediction mode. This prediction mode ignores the current
* parser context when making predictions. This is the fastest prediction
* mode, and provides correct results for many grammars. This prediction
* mode is more powerful than the prediction mode provided by ANTLR 3, but
* may result in syntax errors for grammar and input combinations which are
* not SLL.
*
* When using this prediction mode, the parser will either return a correct
* parse tree (i.e. the same parse tree that would be returned with the
* {@link #LL} prediction mode), or it will report a syntax error. If a
* syntax error is encountered when using the {@link #SLL} prediction mode,
* it may be due to either an actual syntax error in the input or indicate
* that the particular combination of grammar and input requires the more
* powerful {@link #LL} prediction abilities to complete successfully.
*
* This prediction mode does not provide any guarantees for prediction
* behavior for syntactically-incorrect inputs.
*/
PredictionMode[PredictionMode["SLL"] = 0] = "SLL";
/**
* The LL(*) prediction mode. This prediction mode allows the current parser
* context to be used for resolving SLL conflicts that occur during
* prediction. This is the fastest prediction mode that guarantees correct
* parse results for all combinations of grammars with syntactically correct
* inputs.
*
* When using this prediction mode, the parser will make correct decisions
* for all syntactically-correct grammar and input combinations. However, in
* cases where the grammar is truly ambiguous this prediction mode might not
* report a precise answer for *exactly which* alternatives are
* ambiguous.
*
* This prediction mode does not provide any guarantees for prediction
* behavior for syntactically-incorrect inputs.
*/
PredictionMode[PredictionMode["LL"] = 1] = "LL";
/**
* The LL(*) prediction mode with exact ambiguity detection. In addition to
* the correctness guarantees provided by the {@link #LL} prediction mode,
* this prediction mode instructs the prediction algorithm to determine the
* complete and exact set of ambiguous alternatives for every ambiguous
* decision encountered while parsing.
*
* This prediction mode may be used for diagnosing ambiguities during
* grammar development. Due to the performance overhead of calculating sets
* of ambiguous alternatives, this prediction mode should be avoided when
* the exact results are not necessary.
*
* This prediction mode does not provide any guarantees for prediction
* behavior for syntactically-incorrect inputs.
*/
PredictionMode[PredictionMode["LL_EXACT_AMBIG_DETECTION"] = 2] = "LL_EXACT_AMBIG_DETECTION";
})(PredictionMode = exports.PredictionMode || (exports.PredictionMode = {}));
(function (PredictionMode) {
/** A Map that uses just the state and the stack context as the key. */
// NOTE: Base type used to be FlexibleHashMap<ATNConfig, BitSet>
class AltAndContextMap extends Array2DHashMap_1.Array2DHashMap {
constructor() {
super(AltAndContextConfigEqualityComparator.INSTANCE);
}
}
class AltAndContextConfigEqualityComparator {
AltAndContextConfigEqualityComparator() {
// intentionally empty
}
/**
* The hash code is only a function of the {@link ATNState#stateNumber}
* and {@link ATNConfig#context}.
*/
hashCode(o) {
let hashCode = MurmurHash_1.MurmurHash.initialize(7);
hashCode = MurmurHash_1.MurmurHash.update(hashCode, o.state.stateNumber);
hashCode = MurmurHash_1.MurmurHash.update(hashCode, o.context);
hashCode = MurmurHash_1.MurmurHash.finish(hashCode, 2);
return hashCode;
}
equals(a, b) {
if (a === b) {
return true;
}
if (a == null || b == null) {
return false;
}
return a.state.stateNumber === b.state.stateNumber
&& a.context.equals(b.context);
}
}
AltAndContextConfigEqualityComparator.INSTANCE = new AltAndContextConfigEqualityComparator();
__decorate([
Decorators_1.Override
], AltAndContextConfigEqualityComparator.prototype, "hashCode", null);
__decorate([
Decorators_1.Override
], AltAndContextConfigEqualityComparator.prototype, "equals", null);
/**
* Checks if any configuration in `configs` is in a
* {@link RuleStopState}. Configurations meeting this condition have reached
* the end of the decision rule (local context) or end of start rule (full
* context).
*
* @param configs the configuration set to test
* @returns `true` if any configuration in `configs` is in a
* {@link RuleStopState}, otherwise `false`
*/
function hasConfigInRuleStopState(configs) {
for (let c of configs) {
if (c.state instanceof RuleStopState_1.RuleStopState) {
return true;
}
}
return false;
}
PredictionMode.hasConfigInRuleStopState = hasConfigInRuleStopState;
/**
* Checks if all configurations in `configs` are in a
* {@link RuleStopState}. Configurations meeting this condition have reached
* the end of the decision rule (local context) or end of start rule (full
* context).
*
* @param configs the configuration set to test
* @returns `true` if all configurations in `configs` are in a
* {@link RuleStopState}, otherwise `false`
*/
function allConfigsInRuleStopStates(/*@NotNull*/ configs) {
for (let config of configs) {
if (!(config.state instanceof RuleStopState_1.RuleStopState)) {
return false;
}
}
return true;
}
PredictionMode.allConfigsInRuleStopStates = allConfigsInRuleStopStates;
})(PredictionMode = exports.PredictionMode || (exports.PredictionMode = {}));
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