57 lines
1.7 KiB
JavaScript
57 lines
1.7 KiB
JavaScript
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/* We can insert data into the PreloadStore when the document is loaded.
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The data can be accessed once by a key, after which it is removed */
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(function() {
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window.PreloadStore = {
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data: {},
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store: function(key, value) {
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this.data[key] = value;
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},
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/* To retrieve a key, you provide the key you want, plus a finder to
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load it if the key cannot be found. Once the key is used once, it is
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removed from the store. So, for example, you can't load a preloaded topic
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more than once. */
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get: function(key, finder) {
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var promise, result;
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promise = new RSVP.Promise();
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if (this.data[key]) {
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promise.resolve(this.data[key]);
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delete this.data[key];
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} else {
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if (finder) {
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result = finder();
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// If the finder returns a promise, we support that too
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if (result.then) {
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result.then(function(result) {
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return promise.resolve(result);
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}, function(result) {
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return promise.reject(result);
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});
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} else {
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promise.resolve(result);
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}
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} else {
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promise.resolve(void 0);
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}
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}
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return promise;
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},
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/* Does the store contain a particular key? Does not delete, just returns
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true or false. */
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contains: function(key) {
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return this.data[key] !== void 0;
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},
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/* If we are sure it's preloaded, we don't have to supply a finder. Just
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returns undefined if it's not in the store. */
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getStatic: function(key) {
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var result;
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result = this.data[key];
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delete this.data[key];
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return result;
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}
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};
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}).call(this);
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