91 lines
2.7 KiB
JavaScript
91 lines
2.7 KiB
JavaScript
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'use strict';
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var clear = require('es5-ext/array/#/clear')
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, assign = require('es5-ext/object/assign')
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, callable = require('es5-ext/object/valid-callable')
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, value = require('es5-ext/object/valid-value')
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, d = require('d')
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, autoBind = require('d/auto-bind')
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, Symbol = require('es6-symbol')
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, defineProperty = Object.defineProperty
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, defineProperties = Object.defineProperties
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, Iterator;
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module.exports = Iterator = function (list, context) {
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if (!(this instanceof Iterator)) return new Iterator(list, context);
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defineProperties(this, {
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__list__: d('w', value(list)),
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__context__: d('w', context),
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__nextIndex__: d('w', 0)
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});
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if (!context) return;
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callable(context.on);
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context.on('_add', this._onAdd);
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context.on('_delete', this._onDelete);
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context.on('_clear', this._onClear);
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};
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defineProperties(Iterator.prototype, assign({
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constructor: d(Iterator),
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_next: d(function () {
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var i;
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if (!this.__list__) return;
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if (this.__redo__) {
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i = this.__redo__.shift();
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if (i !== undefined) return i;
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}
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if (this.__nextIndex__ < this.__list__.length) return this.__nextIndex__++;
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this._unBind();
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}),
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next: d(function () { return this._createResult(this._next()); }),
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_createResult: d(function (i) {
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if (i === undefined) return { done: true, value: undefined };
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return { done: false, value: this._resolve(i) };
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}),
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_resolve: d(function (i) { return this.__list__[i]; }),
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_unBind: d(function () {
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this.__list__ = null;
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delete this.__redo__;
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if (!this.__context__) return;
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this.__context__.off('_add', this._onAdd);
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this.__context__.off('_delete', this._onDelete);
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this.__context__.off('_clear', this._onClear);
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this.__context__ = null;
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}),
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toString: d(function () { return '[object Iterator]'; })
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}, autoBind({
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_onAdd: d(function (index) {
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if (index >= this.__nextIndex__) return;
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++this.__nextIndex__;
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if (!this.__redo__) {
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defineProperty(this, '__redo__', d('c', [index]));
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return;
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}
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this.__redo__.forEach(function (redo, i) {
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if (redo >= index) this.__redo__[i] = ++redo;
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}, this);
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this.__redo__.push(index);
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}),
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_onDelete: d(function (index) {
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var i;
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if (index >= this.__nextIndex__) return;
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--this.__nextIndex__;
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if (!this.__redo__) return;
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i = this.__redo__.indexOf(index);
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if (i !== -1) this.__redo__.splice(i, 1);
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this.__redo__.forEach(function (redo, i) {
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if (redo > index) this.__redo__[i] = --redo;
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}, this);
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}),
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_onClear: d(function () {
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if (this.__redo__) clear.call(this.__redo__);
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this.__nextIndex__ = 0;
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})
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})));
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defineProperty(Iterator.prototype, Symbol.iterator, d(function () {
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return this;
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}));
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defineProperty(Iterator.prototype, Symbol.toStringTag, d('', 'Iterator'));
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