HaxeFoundation.haxe/std/js/lib/Symbol.hx

/*
 * Copyright (C)2005-2019 Haxe Foundation
 *
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 * copy of this software and associated documentation files (the "Software"),
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 * 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,
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 */

package js.lib;

@:native("Symbol")
extern class Symbol {
	/**
		To create a new primitive symbol, use `new Symbol()` with an optional string as its `description`.

		NOTE: Unlike in plain JavaScript, `new Symbol()` syntax is used in Haxe. This generates a `Symbol(...)`
		expression as required by the JavaScript specification.
	**/
	@:pure @:selfCall function new(?description:String);

	/**
		Searches for existing symbols with the given key and returns it if found.
		Otherwise a new symbol gets created in the global symbol registry with this key.
	**/
	@:native("for") static function for_(key:String):Symbol;

	/**
		Retrieves a shared symbol key from the global symbol registry for the given symbol.
	**/
	@:pure static function keyFor(sym:Symbol):Null<String>;

	/**
		Returns a string containing the description of the Symbol.
	**/
	@:pure function toString():String;

	/**
		A method returning the default iterator for an object.
	**/
	static var iterator(default, null):Symbol;

	/**
		A method that returns the default AsyncIterator for an object.
	**/
	static var asyncIterator(default, null):Symbol;

	/**
		Retrieve symbol from a given `object`.

		NOTE: This is a Haxe-specific method that generates an `object[symbol]` expression.
	**/
	inline function ofObject<T>(object:{}):Null<T>
		return (cast object)[cast this];
}