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antlr4ng

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Alternative JavaScript/TypeScript runtime for ANTLR4

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import { TokenStream } from "../TokenStream.js"; import { ATNConfigSet } from "./ATNConfigSet.js"; /** * This is the base class for gathering detailed information about prediction * events which occur during parsing. * * Note that we could record the parser call stack at the time this event * occurred but in the presence of left recursive rules, the stack is kind of * meaningless. It's better to look at the individual configurations for their * individual stacks. Of course that is a {@link PredictionContext} object * not a parse tree node and so it does not have information about the extent * (start...stop) of the various subtrees. Examining the stack tops of all * configurations provide the return states for the rule invocations. * From there you can get the enclosing rule. */ export interface DecisionEventInfo { /** * The invoked decision number which this event is related to. * * @see ATN#decisionToState */ decision: number; /** * The configuration set containing additional information relevant to the * prediction state when the current event occurred, or `null` if no * additional information is relevant or available. */ configs: ATNConfigSet | null; /** * The input token stream which is being parsed. */ input: TokenStream; /** * The token index in the input stream at which the current prediction was * originally invoked. */ startIndex: number; /** * The token index in the input stream at which the current event occurred. */ stopIndex: number; /** * `true` if the current event occurred during LL prediction; * otherwise, `false` if the input occurred during SLL prediction. */ fullCtx: boolean; }