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/**
* @author Titus Wormer
* @copyright 2016 Titus Wormer
* @license MIT
* @module state-toggle
* @fileoverview Enter/exit a state.
*/
'use strict';
/* eslint-env commonjs */
/* Expose. */
module.exports = factory;
/**
* Construct a state `toggler`: a function which inverses
* `property` in context based on its current value.
* The by `toggler` returned function restores that value.
*
* @param {string} key - Property to toggle.
* @param {boolean} state - Default state.
* @param {Object?} [ctx] - Context object.
* @return {Function} - Enter.
*/
function factory(key, state, ctx) {
/**
* Enter a state.
*
* @return {Function} - Exit state.
*/
return function () {
var context = ctx || this;
var current = context[key];
context[key] = !state;
/**
* Cancel state to its value before entering.
*/
return function () {
context[key] = current;
};
};
}