Run results for: numeric vs string property accessor

Test name	Executions per second
✓ numeric keys	109,722 Ops/sec
string keys, with key caching	48,385 Ops/sec
string keys	35,273 Ops/sec

Script Preparation code:

/*your preparation JavaScript code goes here
To execute async code during the script preparation, wrap it as function globalMeasureThatScriptPrepareFunction, example:*/
async function globalMeasureThatScriptPrepareFunction() {
    // This function is optional, feel free to remove it.
    // await someThing();
}

Tests:

numeric keys
let o = {}; // write for (let n=1; n <= 1000; n++) { if (o[n] === undefined) o[n] = n; } // read let sum = 0; for (let n=1; n <= 1000; n++) { if (o[n] !== undefined) sum += o[n]; } //console.log("numeric keys - sum ", sum); // expects 500500 (1 - 1000)
string keys
let o = {}; // write for (let n=1; n <= 1000; n++) { if (o[n.toString()] === undefined) o[n.toString()] = n; } // read let sum = 0; for (let n=1; n <= 1000; n++) { if (o[n.toString()] !== undefined) sum += o[n.toString()]; } //console.log("string keys - sum ", sum); // expects 500500 (1 - 1000)
string keys, with key caching (n.toString())
let o = {}; let k; // write for (let n=1; n <= 1000; n++) { k = n.toString(); if (o[k] === undefined) o[k] = n; } // read let sum = 0; for (let n=1; n <= 1000; n++) { k = n.toString(); if (o[k] !== undefined) sum += o[k]; } //console.log("string keys - sum ", sum); // expects 500500 (1 - 1000)
string keys, with key caching ("" + n)
let o = {}; let k; // write for (let n=1; n <= 1000; n++) { k = "" + n; if (o[k] === undefined) o[k] = n; } // read let sum = 0; for (let n=1; n <= 1000; n++) { k = "" + n; if (o[k] !== undefined) sum += o[k]; } //console.log("string keys - sum ", sum); // expects 500500 (1 - 1000)

Run results for: numeric vs string property accessor

compare setting and getting values of property accessed via numeric key and string key

numeric keys

string keys

string keys, with key caching (n.toString())

string keys, with key caching ("" + n)