Benchmark: filter + map vs conditional + foreach

Script Preparation code:

var arr = Array.from(new Array(999)).map((d,i) => i);

Tests:

filter + map
var result = arr.filter(d => d%2).map(d => d * 2);
conditional + forEach
var result = []; arr.forEach(d => { if (d%2) { result.push(d * 2); } });

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
filter + map
conditional + forEach

Fastest: N/A

Slowest: N/A

Latest run results:

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Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and explain what's being tested.

**Benchmark Definition**

The benchmark is designed to compare two approaches for processing an array of numbers:

1. **Filter + Map**: This approach uses the `Array.prototype.filter()` method to create a new array with only the elements that pass a test (in this case, `d % 2 === 0`). Then, it uses the `Array.prototype.map()` method to apply a transformation to each element in the filtered array.
2. **Conditional + Foreach**: This approach uses the `forEach()` method to iterate over the original array and conditionally push elements to a new array if they meet a certain condition (in this case, `d % 2 === 0`).

**Options Compared**

The benchmark compares the performance of these two approaches:

* Filter + Map: A single pass through the data using filtering and mapping.
* Conditional + Foreach: Multiple passes through the data using looping and conditional checks.

**Pros and Cons of Each Approach**

**Filter + Map**

Pros:

* Fewer iterations over the data, which can lead to better performance.
* Uses modern JavaScript methods that are optimized for efficiency.

Cons:

* Requires creating a new array, which can consume memory.
* May have overhead due to method calls and object creation.

**Conditional + Foreach**

Pros:

* Can be more flexible and adaptable to different data structures and requirements.
* Does not require creating a new array.

Cons:

* More iterations over the data, which can lead to slower performance.
* Uses older JavaScript methods that may not be as efficient.

**Library Usage**

The benchmark uses the `Array.prototype.filter()` and `Array.prototype.map()` methods, which are built-in functions in JavaScript. These methods are designed to work efficiently with arrays and are implemented in native code, making them fast and memory-efficient.

No external libraries are used in this benchmark.

**Special JS Features or Syntax**

There are no special JavaScript features or syntax mentioned in the benchmark definition. However, it's worth noting that the use of `let` and arrow functions (`=>`) is not considered experimental or deprecated.

**Other Alternatives**

Other alternatives to consider for processing arrays include:

* Using a library like Lodash or Ramda, which provide more functional programming features and can simplify certain operations.
* Implementing custom loops using for...of or for...in loops, but this would likely be slower than the built-in filter() and map() methods.

It's worth noting that the choice of approach often depends on the specific use case, data structure, and performance requirements.

Related benchmarks:

filter + map vs conditional + foreach (version: 0)

Compare chained `array.filter().map()` vs creating a new array, looping through the previous one and conditionally pushing to it.

Comparing performance of: filter + map vs conditional + forEach

Created: 6 years ago by: Guest

Jump to the latest result

filter + map

conditional + forEach

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):