var arr='giyrxgfoyugrxeupqzuehfgfccsydgfpxwieuhqzuiehfuiegfyuegfpegrygrypiop634927chmiuqefdyiqdetfcityrfiwecfiuegciquegiyrxgfoyugrxeupqzuehfgfccsydgfpxwieuhqzuiehfuiegfyuegfpegrygrypiop634927chmiuqefdyiqdetfcityrfiwecfiuegciquegiyrxgfoyugrxeupqzuehfgfccsydgfpxwieuhqzuiehfuiegfyuegfpegrygrypiop634927chmiuqefdyiqdetfcityrfiwecfiuegciquegiyrxgfoyugrxeupqzuehfgfccsydgfpxwieuhqzuiehfuiegfyuegfpegrygrypiop634927chmiuqefdyiqdetfcityrfiwecfiuegciquegiyrxgfoyugrxeupqzuehfgfccsydgfpxwieuhqzuiehfuiegfyuegfpegrygrypiop634927chmiuqefdyiqdetfcityrfiwecfiuegciquegiyrxgfoyugrxeupqzuehfgfccsydgfpxwieuhqzuiehfuiegfyuegfpegrygrypiop634927chmiuqefdyiqdetfcityrfiwecfiuegciquegiyrxgfoyugrxeupqzuehfgfccsydgfpxwieuhqzuiehfuiegfyuegfpegrygrypiop634927chmiuqefdyiqdetfcityrfiwecfiuegciquegiyrxgfoyugrxeupqzuehfgfccsydgfpxwieuhqzuiehfuiegfyuegfpegrygrypiop634927chmiuqefdyiqdetfcityrfiwecfiuegciqueieuhqzuiehfuiegfyuegfpegrygrypiop634927chmiuqefdyiqdetfcityrfiwecfiuegciquegiyrxgfoyugrxeupqzuehfgfccsydgfpxwieuhqzuiehfuiegfyui'.split('');
var a;
const k = (b) => {a=b}
for(let i=0; i < 1000; ){k(arr[i++])};
arr.forEach((b)=>{a=b});
--enable-precise-memory-info
flag.
Test case name | Result |
---|---|
for | |
foreach |
Test name | Executions per second |
---|---|
for | 5197.5 Ops/sec |
foreach | 9414.8 Ops/sec |
Measuring the performance of different JavaScript iteration techniques is an essential task for any web developer or JavaScript enthusiast.
Benchmark Definition
The provided benchmark definition json describes two individual test cases: "for" and "foreach". Both test cases aim to measure the performance of iterating over an array using two different methods.
Benchmark Definition
script uses a traditional for loop (for(let i=0; i < 1000; ){k(arr[i++])};
) with a function k
that takes an element from the array and assigns it to variable a
.Benchmark Definition
script uses the forEach
method on the arr
array, which iterates over each element in the array and calls a provided callback function (in this case, (b)=>{a=b};
) for each iteration.Options Compared
The benchmark compares two options:
for
): This is a manual loop that increments a counter variable until it reaches the end of the array.forEach
: This method iterates over each element in the array and calls a callback function for each iteration.Pros and Cons
For Loop (for
) Pros:
Cons:
Array Method forEach
Pros:
Cons:
Other Considerations
When choosing between these two options, consider the following factors:
forEach
are faster than traditional for loops because they are implemented in optimized C++ code. However, this difference is usually negligible unless you're dealing with very large arrays or performance-critical code.forEach
can make your code more concise and readable, especially when working with large datasets.Library Used
In the provided benchmark definition json, no specific library is used. However, it's worth noting that some JavaScript engines (e.g., V8) have built-in optimizations for array iteration, which may affect the performance difference between these two options.
Special JS Feature or Syntax
The forEach
method in JavaScript is a built-in method for iterating over arrays and other iterable objects. It was introduced in ECMAScript 2015 (ES6).
Alternatives
If you need to iterate over data structures other than arrays, consider using:
for
): Suitable for any type of data structure.map
, filter
**: Designed for transforming and filtering arrays, respectively.forEach
, clear()
, etc.In conclusion, the choice between a traditional for loop and an array method like forEach
depends on your specific use case, performance requirements, and personal preference.