Benchmark: js array comparison - for vs find vs map vs foreach

HTML Preparation code:

<!--your preparation HTML code goes here-->

Script Preparation code:

var arr = []
let i = 0
let len = 1000
for (; i < len; i++) {
    arr.push({
        ID: i,
        TestName: "Name"
    })
}

Tests:

For
let i = 0 let len = arr.length let foundIndex = -1 for (; i < len; i++) { if (arr[i].ID >= 999) { return arr[i] } }
find
const found = arr.find(function(element) { if(element.ID > 999){ return element }})
map
let foundMapIndex = arr.map(item => { if (item.ID > 999){ return i }})

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
For
find
map

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 months ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/133.0.0.0 Safari/537.36

Browser/OS: Chrome 133 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
For	609757.5 Ops/sec
find	985587.8 Ops/sec
map	347235.5 Ops/sec

Autogenerated LLM Summary (model gpt-4o-mini, generated 2 months ago):

LLMs can make mistakes. Check important info.

The benchmark defined in the provided JSON is focused on comparing the performance of four different approaches to search through an array of objects in JavaScript. The options compared are: traditional `for` loop, `Array.prototype.find()` method, and `Array.prototype.map()` method. Here's a breakdown of each approach, their pros and cons, and other considerations:

### Approaches Compared

1. **For Loop**
   - **Benchmark Definition**: 
     ```javascript
     let i = 0;
     let len = arr.length;
     let foundIndex = -1;
     for (; i < len; i++) {
         if (arr[i].ID >= 999) {
             return arr[i];
         }
     }
     ```
   - **Pros**:
     - Highly performant for large datasets because it operates in a straightforward, sequential manner.
     - Greater control over the iteration process, allowing for early exits (via return).
   - **Cons**:
     - More verbose and less readable than declarative approaches.
     - More susceptible to off-by-one errors and bugs due to manual index management.

2. **Array.prototype.find()**
   - **Benchmark Definition**: 
     ```javascript
     const found = arr.find(function(element) {
         if (element.ID > 999) {
             return element;
         }
     });
     ```
   - **Pros**:
     - More readable and expressive, making it clear that the intention is to find an element.
     - Automatically handles the iteration and encapsulates the logic, reducing boilerplate code.
   - **Cons**:
     - Slightly less performant compared to `for` loops, as it may involve more overhead due to function calls.
     - It returns the first matched element; if you specifically need the index or need to process all matches, this is not suitable.

3. **Array.prototype.map()**
   - **Benchmark Definition**: 
     ```javascript
     let foundMapIndex = arr.map(item => {
         if (item.ID > 999) {
             return i;
         }
     });
     ```
   - **Pros**:
     - Functional and declarative style, which can lead to cleaner and easier-to-understand code.
     - Generates a new array based on the transformation applied to each element, useful for further processing.
   - **Cons**:
     - Inappropriate for searching since it is designed for transformation (returning a new array), not for finding values.
     - Potentially the least performant due to unnecessary array creation, making it a poor choice for this specific use case.

### Alternative Approaches

While the benchmark covers these three common methods, several alternatives exist for searching within arrays in JavaScript:

- **`Array.prototype.filter()`**: This can be used if multiple matches need to be found. It processes every element of the array and returns an array of all elements that satisfy the condition. However, like `map()`, it is not the most performant option for a simple search.

- **`forEach()`**: Similar to `map()`, `forEach()` iterates over each element but doesn't return a new array; instead, it is generally used for executing a function on each element. It lacks a return value useful for searching scenarios.

- **`reduce()`**: This method can also be employed for searching, but it is more complex and generally used when accumulating results from an array rather than for beam-finding tasks.

### Considerations
- **Performance**: The choice of method can significantly impact performance, especially with large datasets. Hence, choosing the right tool for the job based on the expected workload is critical.
- **Readability**: In many cases, readability and maintainability should also be taken into account when selecting an approach, as code that is easier to understand can reduce errors and facilitate collaboration in teams.
- **Use Cases**: The selection of method may often depend on the specific use case at hand, such as needing only the first match, all matches, or simply processing each element in some way.

In conclusion, while the benchmark compares a few common approaches to searching through an array in JavaScript, understanding the appropriate use cases, performance implications, and the trade-offs in code readability will guide engineers toward making informed decisions in their implementations.

Related benchmarks:

js array comparison - for vs find vs map vs foreach (version: 1)

Comparing performance of: for vs prototype.find vs forEach vs map

Comparing performance of: For vs find vs map

Created: 2 months ago by: Guest

Jump to the latest result

For

find

map

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model gpt-4o-mini, generated 2 months ago):