isTypedArray - instanceOf vs .constructor checks

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isTypedArray - instanceOf vs .constructor checks

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{"title":"isTypedArray - instanceOf vs .constructor checks","initialization":"// runs once\n\nfunction isTypedArraySwitch(v) {\n\tswitch(v.constructor){\n\t\tcase Uint8ClampedArray:\n\t\tcase Uint8Array:\n\t\tcase Uint16Array:\n\t\tcase Uint32Array:\n\t\tcase Int8Array:\n\t\tcase Int16Array:\n\t\tcase Int32Array:\n\t\tcase Float32Array:\n\t\tcase Float64Array:\n\t\tcase BigInt64Array:\n\t\tcase BigUint64Array:\n\t\treturn true;\n\t\tdefault: return false;\n}\n}\n\nconst isTypedArrayIndexOf = (() => {\n\tconst taConstructors = [Uint8ClampedArray, Uint8Array, Uint16Array, Uint32Array, Int8Array, Int16Array, Int32Array, Float32Array, Float64Array, BigInt64Array, BigUint64Array];\n\treturn function isTypedArrayIndexOf(v = 0) {\n\t\treturn taConstructors.indexOf(v.constructor) !== -1\n\t}\n})();\n\nconst isTypedArrayMap = (() => {\n\tconst taConstructors = new Map();\n\t[Uint8ClampedArray, Uint8Array, Uint16Array, Uint32Array, Int8Array, Int16Array, Int32Array, Float32Array, Float64Array, BigInt64Array, BigUint64Array].map(constr => taConstructors.set(constr, true));\n\t\n\treturn function isTypedArrayMap(v = 0) {\n\t\treturn taConstructors.get(v.constructor) === true;\n\t}\n})();\n\n\n\nconst isTypedArrayWeakMap = (() => {\n\tconst taConstructors = new WeakMap();\n\t[Uint8ClampedArray, Uint8Array, Uint16Array, Uint32Array, Int8Array, Int16Array, Int32Array, Float32Array, Float64Array, BigInt64Array, BigUint64Array].map(constr => taConstructors.set(constr, true));\n\t\n\treturn function isTypedArrayMap(v = 0) {\n\t\treturn taConstructors.get(v.constructor) === true;\n\t}\n})();\n\nfunction isTypedArrayInstanceOf(v) {\n\treturn (v instanceof Uint8ClampedArray) ||\n           (v instanceof Uint8Array) ||\n           (v instanceof Uint16Array) ||\n           (v instanceof Uint32Array) ||\n           (v instanceof Int8Array) ||\n           (v instanceof Int16Array) ||\n           (v instanceof Int32Array) ||\n           (v instanceof Float32Array) ||\n           (v instanceof Float64Array) ||\n           (v instanceof BigInt64Array) ||\n           (v instanceof BigUint64Array);\n}\n\nfunction isTypedArrayHasArrayBuffer(v) {\n  return v.buffer ? (v.buffer instanceof ArrayBuffer) : false;\n}\n\nfunction isTypedArrayHasArrayBuffer2(v) {\n  return v.buffer ? (v.buffer.constructor === ArrayBuffer) : false;\n}\n\nfunction isTypedArrayHasArrayBuffer3(v) {\n  return (v.buffer ?? \"\").constructor === ArrayBuffer;\n}\n\nfunction isTypedArrayHasArrayBuffer4(v) {\n  return v?.buffer?.constructor === ArrayBuffer;\n}\n\nfunction generateRandomTypedArrays(){\n\tconst taConstructors = [Uint8ClampedArray, Uint8Array, Uint16Array, Uint32Array, Int8Array, Int16Array, Int32Array, Float32Array, Float64Array, BigInt64Array, BigUint64Array];\n\n\tconst arrays = [];\n\tfor (let i = 0; i < 1000; i++) {\n\t\tarrays[i] = Math.random() < 0.5 ? new (taConstructors[taConstructors.length * Math.random() | 0])() : 0;\n\t}\n\treturn arrays;\n}","setup":"// runs before each test\n\nconst arrays = generateRandomTypedArrays();\nconst isTA = [false];\nfor (let i = 0; i < arrays.length; i++) isTA[i] = false;","tests":[{"name":"Constructor equality + switch","code":"// Constructor equality + switch\nfor (let i = 0; i < arrays.length; i++) isTA[i] = isTypedArraySwitch(arrays[i]);","results":{"aborted":false,"count":5001,"cycles":4,"hz":61465.95916017787,"stats":{"moe":2.532274102034593e-7,"rme":1.5564865653803437,"sem":1.2919765826707107e-7,"deviation":0.0000010335812661365686,"mean":0.000016269167742002356,"variance":1.0682902337084723e-12,"numSamples":64},"times":{"cycle":0.08136210787775378,"elapsed":6.056,"period":0.000016269167742002356,"timeStamp":1723114791460}},"platforms":{"Mozilla/5.0 (X11; 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i < arrays.length; i++) isTA[i] = isTypedArrayIndexOf(arrays[i]);","results":{"aborted":false,"count":2977,"cycles":4,"hz":36669.97628192348,"stats":{"moe":4.628099832327097e-7,"rme":1.697123110818087,"sem":2.361275424656682e-7,"deviation":0.0000018890203397253457,"mean":0.000027270265797607057,"variance":3.5683978438960606e-12,"numSamples":64},"times":{"cycle":0.08118358127947621,"elapsed":6.004,"period":0.000027270265797607057,"timeStamp":1723114797521}},"platforms":{"Mozilla/5.0 (X11; Linux x86_64; rv:129.0) Gecko/20100101 Firefox/129.0":{"aborted":false,"count":2213,"cycles":3,"hz":27534.80003567169,"stats":{"moe":3.813814804770639e-7,"rme":1.0501262802244382,"sem":1.94582387998502e-7,"deviation":0.000001556659103988016,"mean":0.00003631767794588982,"variance":2.4231875660287728e-12,"numSamples":64},"times":{"cycle":0.08037102129425418,"elapsed":5.871,"period":0.00003631767794588982,"timeStamp":1723114715298}},"Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/127.0.0.0 Safari/537.36":{"aborted":false,"count":2977,"cycles":4,"hz":36669.97628192348,"stats":{"moe":4.628099832327097e-7,"rme":1.697123110818087,"sem":2.361275424656682e-7,"deviation":0.0000018890203397253457,"mean":0.000027270265797607057,"variance":3.5683978438960606e-12,"numSamples":64},"times":{"cycle":0.08118358127947621,"elapsed":6.004,"period":0.000027270265797607057,"timeStamp":1723114797521}}}},{"name":"Constructor equality + Map","code":"// Constructor equality + Map\nfor (let i = 0; i < arrays.length; i++) isTA[i] = isTypedArrayMap(arrays[i]);","results":{"aborted":false,"count":3198,"cycles":4,"hz":39943.80616945425,"stats":{"moe":3.34627258168187e-7,"rme":1.3366286339285989,"sem":1.7072819294295255e-7,"deviation":0.0000013764546964073289,"mean":0.000025035170553293893,"variance":1.8946275312617917e-12,"numSamples":65},"times":{"cycle":0.08006247542943387,"elapsed":6.018,"period":0.000025035170553293893,"timeStamp":1723114803530}},"platforms":{"Mozilla/5.0 (X11; Linux x86_64; rv:129.0) Gecko/20100101 Firefox/129.0":{"aborted":false,"count":2443,"cycles":4,"hz":31453.494991597083,"stats":{"moe":2.786421192088895e-7,"rme":0.8764268500984804,"sem":1.4216434653514773e-7,"deviation":0.000001163665327972907,"mean":0.000031792969279476055,"variance":1.3541169955262934e-12,"numSamples":67},"times":{"cycle":0.07767022394976,"elapsed":6.097,"period":0.000031792969279476055,"timeStamp":1723114721174}},"Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/127.0.0.0 Safari/537.36":{"aborted":false,"count":3198,"cycles":4,"hz":39943.80616945425,"stats":{"moe":3.34627258168187e-7,"rme":1.3366286339285989,"sem":1.7072819294295255e-7,"deviation":0.0000013764546964073289,"mean":0.000025035170553293893,"variance":1.8946275312617917e-12,"numSamples":65},"times":{"cycle":0.08006247542943387,"elapsed":6.018,"period":0.000025035170553293893,"timeStamp":1723114803530}}}},{"name":"instanceof","code":"// instanceof\nfor (let i = 0; i < arrays.length; i++) isTA[i] = isTypedArrayInstanceOf(arrays[i]);","results":{"aborted":false,"count":4222,"cycles":8,"hz":52578.08539560226,"stats":{"moe":1.5686709634463457e-7,"rme":0.8247771587368363,"sem":8.003423282889519e-8,"deviation":6.452566137538903e-7,"mean":0.000019019330819597362,"variance":4.163560975931371e-13,"numSamples":65},"times":{"cycle":0.08029961472034006,"elapsed":6.127,"period":0.000019019330819597362,"timeStamp":1723114809553}},"platforms":{"Mozilla/5.0 (X11; Linux x86_64; rv:129.0) Gecko/20100101 Firefox/129.0":{"aborted":false,"count":1734,"cycles":7,"hz":12528.470669189746,"stats":{"moe":0.00003295505920109958,"rme":41.28764926023877,"sem":0.000016813805714846726,"deviation":0.00010896591499132985,"mean":0.00007981820179052014,"variance":1.1873570629897723e-8,"numSamples":42},"times":{"cycle":0.13840476190476192,"elapsed":6.568,"period":0.00007981820179052014,"timeStamp":1723114727276}},"Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/127.0.0.0 Safari/537.36":{"aborted":false,"count":4222,"cycles":8,"hz":52578.08539560226,"stats":{"moe":1.5686709634463457e-7,"rme":0.8247771587368363,"sem":8.003423282889519e-8,"deviation":6.452566137538903e-7,"mean":0.000019019330819597362,"variance":4.163560975931371e-13,"numSamples":65},"times":{"cycle":0.08029961472034006,"elapsed":6.127,"period":0.000019019330819597362,"timeStamp":1723114809553}}}},{"name":"ArrayBuffer instanceof","code":"// ArrayBuffer instanceof\nfor (let i = 0; i < arrays.length; i++) isTA[i] = isTypedArrayHasArrayBuffer(arrays[i]);","results":{"aborted":false,"count":2257,"cycles":5,"hz":27178.40264575983,"stats":{"moe":4.990608770044473e-7,"rme":1.3563677459972894,"sem":2.5462289643084046e-7,"deviation":0.000002021006586176879,"mean":0.000036793921005361676,"variance":4.084467621370322e-12,"numSamples":63},"times":{"cycle":0.0830438797091013,"elapsed":5.963,"period":0.000036793921005361676,"timeStamp":1723114815685}},"platforms":{"Mozilla/5.0 (X11; Linux x86_64; rv:129.0) Gecko/20100101 Firefox/129.0":{"aborted":false,"count":1983,"cycles":4,"hz":19679.926298625887,"stats":{"moe":0.0000034925323739063333,"rme":6.873277971404154,"sem":0.0000017819042724011905,"deviation":0.000012345394936091657,"mean":0.00005081319842492617,"variance":1.5240877612807756e-10,"numSamples":48},"times":{"cycle":0.10076257247662859,"elapsed":5.938,"period":0.00005081319842492617,"timeStamp":1723114733850}},"Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/127.0.0.0 Safari/537.36":{"aborted":false,"count":2257,"cycles":5,"hz":27178.40264575983,"stats":{"moe":4.990608770044473e-7,"rme":1.3563677459972894,"sem":2.5462289643084046e-7,"deviation":0.000002021006586176879,"mean":0.000036793921005361676,"variance":4.084467621370322e-12,"numSamples":63},"times":{"cycle":0.0830438797091013,"elapsed":5.963,"period":0.000036793921005361676,"timeStamp":1723114815685}}}},{"name":"ArrayBuffer constructor + ternary","code":"// ArrayBuffer constructor + ternary\nfor (let i = 0; i < arrays.length; i++) isTA[i] = isTypedArrayHasArrayBuffer2(arrays[i]);","results":{"aborted":false,"count":2215,"cycles":4,"hz":27761.60780758342,"stats":{"moe":4.2265369859398414e-7,"rme":1.1733546218790758,"sem":2.1563964213978782e-7,"deviation":0.0000017251171371183026,"mean":0.00003602096848752535,"variance":2.9760291367792483e-12,"numSamples":64},"times":{"cycle":0.07978644519986865,"elapsed":5.82,"period":0.00003602096848752535,"timeStamp":1723114821654}},"platforms":{"Mozilla/5.0 (X11; Linux x86_64; rv:129.0) Gecko/20100101 Firefox/129.0":{"aborted":false,"count":1997,"cycles":3,"hz":18375.762102215336,"stats":{"moe":0.000003758066145507095,"rme":6.905732945422774,"sem":0.0000019173806864832116,"deviation":0.00001328400306576086,"mean":0.000054419511660930925,"variance":1.764647374511439e-10,"numSamples":48},"times":{"cycle":0.10867576478687906,"elapsed":5.86,"period":0.000054419511660930925,"timeStamp":1723114739793}},"Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/127.0.0.0 Safari/537.36":{"aborted":false,"count":2215,"cycles":4,"hz":27761.60780758342,"stats":{"moe":4.2265369859398414e-7,"rme":1.1733546218790758,"sem":2.1563964213978782e-7,"deviation":0.0000017251171371183026,"mean":0.00003602096848752535,"variance":2.9760291367792483e-12,"numSamples":64},"times":{"cycle":0.07978644519986865,"elapsed":5.82,"period":0.00003602096848752535,"timeStamp":1723114821654}}}},{"name":"ArrayBuffer constructor + nullish coalescing operator","code":"// ArrayBuffer constructor + nullish coalescing operator\nfor (let i = 0; i < arrays.length; i++) isTA[i] = isTypedArrayHasArrayBuffer3(arrays[i]);","results":{"aborted":false,"count":3252,"cycles":4,"hz":40196.22006513844,"stats":{"moe":2.4942311596425314e-7,"rme":1.0025866458631663,"sem":1.272566918184965e-7,"deviation":0.000001010068677661589,"mean":0.00002487796112120713,"variance":1.0202387335930307e-12,"numSamples":63},"times":{"cycle":0.08090312956616559,"elapsed":5.881,"period":0.00002487796112120713,"timeStamp":1723114827479}},"platforms":{"Mozilla/5.0 (X11; Linux x86_64; rv:129.0) Gecko/20100101 Firefox/129.0":{"aborted":false,"count":2195,"cycles":4,"hz":17730.413285708622,"stats":{"moe":0.000006739728973412412,"rme":11.949818013226675,"sem":0.0000034386372313328632,"deviation":0.000022284916252159412,"mean":0.000056400264555933254,"variance":4.966174923657587e-10,"numSamples":42},"times":{"cycle":0.1237985807002735,"elapsed":5.889,"period":0.000056400264555933254,"timeStamp":1723114745658}},"Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/127.0.0.0 Safari/537.36":{"aborted":false,"count":3252,"cycles":4,"hz":40196.22006513844,"stats":{"moe":2.4942311596425314e-7,"rme":1.0025866458631663,"sem":1.272566918184965e-7,"deviation":0.000001010068677661589,"mean":0.00002487796112120713,"variance":1.0202387335930307e-12,"numSamples":63},"times":{"cycle":0.08090312956616559,"elapsed":5.881,"period":0.00002487796112120713,"timeStamp":1723114827479}}}},{"name":"ArrayBuffer constructor + optional chaining","code":"// ArrayBuffer constructor + optional chaining\nfor (let i = 0; i < arrays.length; i++) isTA[i] = isTypedArrayHasArrayBuffer4(arrays[i]);","results":{"aborted":false,"count":3277,"cycles":4,"hz":41288.80218771943,"stats":{"moe":1.9500627954504013e-7,"rme":0.8051575701498279,"sem":9.949299976787762e-8,"deviation":8.082849511066746e-7,"mean":0.000024219641816042583,"variance":6.533245621855194e-13,"numSamples":66},"times":{"cycle":0.07936776623117155,"elapsed":6.032,"period":0.000024219641816042583,"timeStamp":1723114833366}},"platforms":{"Mozilla/5.0 (X11; Linux x86_64; rv:129.0) Gecko/20100101 Firefox/129.0":{"aborted":false,"count":2224,"cycles":4,"hz":18171.98587271593,"stats":{"moe":0.000006537228148947648,"rme":11.879441756939755,"sem":0.000003335320484156963,"deviation":0.00002161534720390944,"mean":0.000055029758827924024,"variance":4.672232347455556e-10,"numSamples":42},"times":{"cycle":0.12238618363330303,"elapsed":5.901,"period":0.000055029758827924024,"timeStamp":1723114751552}},"Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/127.0.0.0 Safari/537.36":{"aborted":false,"count":3277,"cycles":4,"hz":41288.80218771943,"stats":{"moe":1.9500627954504013e-7,"rme":0.8051575701498279,"sem":9.949299976787762e-8,"deviation":8.082849511066746e-7,"mean":0.000024219641816042583,"variance":6.533245621855194e-13,"numSamples":66},"times":{"cycle":0.07936776623117155,"elapsed":6.032,"period":0.000024219641816042583,"timeStamp":1723114833366}}}},{"name":"Constructor equality + WeakMap","code":"// Constructor equality + WeakMap\nfor (let i = 0; i < arrays.length; i++) isTA[i] = isTypedArrayMap(arrays[i]);","results":{"aborted":false,"count":3197,"cycles":4,"hz":40126.18038546936,"stats":{"moe":3.238490724769511e-7,"rme":1.299482629987708,"sem":1.6522911861068935e-7,"deviation":0.0000013321197417635702,"mean":0.0000249213852500679,"variance":1.7745430063962407e-12,"numSamples":65},"times":{"cycle":0.07967366864446708,"elapsed":6.079,"period":0.0000249213852500679,"timeStamp":1723114839404}},"platforms":{"Mozilla/5.0 (X11; Linux x86_64; rv:129.0) Gecko/20100101 Firefox/129.0":{"aborted":false,"count":2442,"cycles":4,"hz":30345.88205817641,"stats":{"moe":5.123036936179459e-7,"rme":1.554630746449833,"sem":2.6137943551936015e-7,"deviation":0.000002091035484154881,"mean":0.00003295340033560038,"variance":4.372429395994838e-12,"numSamples":64},"times":{"cycle":0.08047220361953612,"elapsed":5.999,"period":0.00003295340033560038,"timeStamp":1723114757458}},"Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/127.0.0.0 Safari/537.36":{"aborted":false,"count":3197,"cycles":4,"hz":40126.18038546936,"stats":{"moe":3.238490724769511e-7,"rme":1.299482629987708,"sem":1.6522911861068935e-7,"deviation":0.0000013321197417635702,"mean":0.0000249213852500679,"variance":1.7745430063962407e-12,"numSamples":65},"times":{"cycle":0.07967366864446708,"elapsed":6.079,"period":0.0000249213852500679,"timeStamp":1723114839404}}}}]}