commonMain.org.antlr.v4.kotlinruntime.tree.ParseTreeProperty.kt Maven / Gradle / Ivy
// Copyright 2017-present Strumenta and contributors, licensed under Apache 2.0.
// Copyright 2024-present Strumenta and contributors, licensed under BSD 3-Clause.
package org.antlr.v4.kotlinruntime.tree
import com.strumenta.antlrkotlin.runtime.IdentityHashMap
/**
* Associate a property with a parse tree node. Useful with parse tree listeners
* that need to associate values with particular tree nodes, kind of like
* specifying a return value for the listener event method that visited a
* particular node. Example:
*
* ```
* val values = ParseTreeProperty()
* values.put(tree, 36)
*
* val x = values.get(tree)
* values.removeFrom(tree)
* ```
*
* You would make one decl (values here) in the listener and use lots of times
* in your event methods.
*/
@Suppress("MemberVisibilityCanBePrivate")
public open class ParseTreeProperty {
protected var annotations: MutableMap = IdentityHashMap()
public operator fun get(node: ParseTree): V? =
annotations[node]
public fun put(node: ParseTree, value: V) {
annotations[node] = value
}
public fun removeFrom(node: ParseTree): V? =
annotations.remove(node)
}