commonMain.org.luaj.vm2.UpValue.kt Maven / Gradle / Ivy
/*******************************************************************************
* Copyright (c) 2009-2011 Luaj.org. All rights reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* THE SOFTWARE.
*/
package org.luaj.vm2
/** Upvalue used with Closure formulation
*
*
* @see LuaClosure
*
* @see Prototype
*/
/**
* Create an upvalue relative to a stack
* @param stack the stack
* @param index the index on the stack for the upvalue
*/
class UpValue(
@kotlin.jvm.JvmField internal var array: Array, // initially the stack, becomes a holder
@kotlin.jvm.JvmField internal var index: Int
) {
/**
* Get the value of the upvalue
* @return the [LuaValue] for this upvalue
*/
/**
* Set the value of the upvalue
* @param value the [LuaValue] to set it to
*/
var value: LuaValue?
get() = array[index]
set(value) { array[index] = value }
override fun toString(): String = "$index/${array.size} ${array[index]}"
/**
* Convert this upvalue to a Java String
* @return the Java String for this upvalue.
* @see LuaValue.tojstring
*/
fun tojstring(): String = array[index]?.tojstring() ?: "null"
/**
* Close this upvalue so it is no longer on the stack
*/
fun close() {
val old = array
array = arrayOf(old[index])
old[index] = null
index = 0
}
}