<script src="https://cdn.jsdelivr.net/lodash/4.16.0/lodash.min.js"></script>
var values = [{
a: 30310
}, {
b: 100303
}, {
c: 3040494
}]
var valArr = [];
for (let i = 0; i < 20000; i++) {
valArr.push({
a: 1,
b: 2,
c: 3
});
}
var count = 0;
_.forEach(valArr, function(v,i) {
if (v.a != null) {
count++;
}
})
var count = 0;
for (let v of valArr) {
if (v.a != null) {
count++;
}
}
--enable-precise-memory-info
flag.
Test case name | Result |
---|---|
lodash.forEach | |
native |
Test name | Executions per second |
---|---|
lodash.forEach | 2565.9 Ops/sec |
native | 25043.0 Ops/sec |
I'll break down the provided benchmark definition and test cases to explain what's being tested.
Benchmark Definition
The provided JSON represents a JavaScript microbenchmark that compares two approaches: forEach
with Lodash library, and a native for...of
loop. The benchmark is designed to measure which approach executes faster on a specific test case.
Options Compared
Two options are compared:
.forEach()
: This uses the _
alias for the Lodash library and calls the forEach()
function on the valArr
array.for...of
loop: This is an iterative approach using a traditional for
loop with the of
keyword to iterate over the elements of the valArr
array.Pros and Cons
Here's a brief overview of the pros and cons of each approach:
Lodash .forEach()
Pros:
Cons:
Native for...of
loop
Pros:
Cons:
Other Considerations
In general, when choosing between these two approaches, consider the trade-offs between simplicity and performance.
If you need to perform frequent iterations over large arrays or datasets, the native for...of
loop might be a better choice due to its potential for better performance. However, if you prioritize code readability and maintainability, the Lodash .forEach()
method can simplify your code.
Library: Lodash
The provided benchmark uses the Lodash library, which is a popular JavaScript utility library that provides various functions for working with arrays, objects, and more. The _.forEach()
function is used to iterate over the elements of an array and perform operations on each element.
Special JS Feature/Syntax (not applicable in this case)
There are no special JavaScript features or syntax introduced in this benchmark beyond what's standard in modern JavaScript implementations.
Alternatives
If you're looking for alternative approaches to iterating over arrays, consider:
.forEach()
, but built into the standard Array prototype.for
loops with manual index management can be a viable option, especially when performance is critical.map()
and forEach()
functions or frameworks like RxJS might provide more suitable alternatives for iterating over data structures.Keep in mind that the choice of iteration approach ultimately depends on your project's specific needs, performance requirements, and codebase conventions.