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Kotlin multiplatform port of ANTLR

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/*
 * Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
 * Use of this file is governed by the BSD 3-clause license that
 * can be found in the LICENSE.txt file in the project root.
 */

package org.antlr.v4.kotlinruntime.atn

import org.antlr.v4.kotlinruntime.TokenStream

/**
 * 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 [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.
 *
 * @since 4.3
 */
open class DecisionEventInfo(
        /**
         * The invoked decision number which this event is related to.
         *
         * @see ATN.decisionToState
         */
        val decision: Int,
        /**
         * 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.
         */
        val configs: ATNConfigSet,
        /**
         * The input token stream which is being parsed.
         */
        val input: TokenStream,
        /**
         * The token index in the input stream at which the current prediction was
         * originally invoked.
         */
        val startIndex: Int,
        /**
         * The token index in the input stream at which the current event occurred.
         */
        val stopIndex: Int,
        /**
         * `true` if the current event occurred during LL prediction;
         * otherwise, `false` if the input occurred during SLL prediction.
         */
        val fullCtx: Boolean)