26 lines
744 B
JavaScript
26 lines
744 B
JavaScript
// ==UserScript==
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// @name Array.at polyfill
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// @run-at document-start
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// @match https://*.linkedin.com/*
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// ==/UserScript==
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// Based on: https://github.com/tc39/proposal-relative-indexing-method#polyfill
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function at(n) {
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// ToInteger() abstract op
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n = Math.trunc(n) || 0;
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// Allow negative indexing from the end
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if (n < 0) n += this.length;
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// OOB access is guaranteed to return undefined
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if (n < 0 || n >= this.length) return undefined;
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// Otherwise, this is just normal property access
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return this[n];
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}
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const TypedArray = Reflect.getPrototypeOf(Int8Array);
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for (const C of [Array, String, TypedArray]) {
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Object.defineProperty(C.prototype, "at",
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{ value: at,
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writable: true,
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enumerable: false,
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configurable: true });
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}
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