var a = Array.from({length: 100}, () => Math.floor(Math.random() * 40));
var b = new Set(a);
return a.includes(98)
return b.has(98)
--enable-precise-memory-info
flag.
Test case name | Result |
---|---|
Includes | |
lookup |
Test name | Executions per second |
---|---|
Includes | 5279192.5 Ops/sec |
lookup | 5273741.0 Ops/sec |
I'll break down the explanation into smaller parts to make it easier to understand.
Benchmark Definition and Script Preparation Code
The provided JSON represents a JavaScript benchmark that tests the performance of two different approaches: array.includes
and set.has
. The script preparation code initializes two arrays:
a
: An array with 100 elements, where each element is a random number between 0 and 39 (inclusive).b
: A Set created from array a
.The purpose of creating these two data structures is to provide a common baseline for the benchmark. The set b
serves as a container for unique values extracted from array a
, which will be used in the subsequent test cases.
Test Cases
There are two individual test cases:
array.includes
method to search for a specific value (98) within array a
. The goal is to measure the performance of this method.set.has
method to check if a specific value (98) exists in set b
. Again, the objective is to evaluate the performance of this approach.Library and Special JS Features
In both test cases:
Array.from()
is used to create an array with 100 random numbers. This function is a modern JavaScript method for creating arrays from iterables.Math.floor(Math.random() * 40)
generates random numbers between 0 and 39 (inclusive). This is a common way to generate random values in JavaScript.Pros and Cons
Here's a brief analysis of the two approaches:
array.includes
when searching for specific values near the beginning of the set.Other Alternatives
Some alternative approaches could have been used:
array.includes
, you could use the indexOf()
method, which returns the index of the specified value. If the value is not found, it returns -1
.set.has
, a more traditional approach would be to use the hasOwnProperty()
method or the in
operator with an object.Keep in mind that these alternatives might have slightly different performance characteristics compared to the original methods used in the benchmark.