Benchmark: [{key, fn}, ...] vs {[key]: fn, ...}

Script Preparation code:

var data = {};
var array = [];
var object = {};
for (var i = 0; i < 1000; i++) {
  var key = Math.random().toString(16).slice(2, 10);
  var fn = function(k) {return data[k];}
  data[key] = Math.random();
  array.push({
    key: key,
    fn: fn
  });
  object[key] = fn;
}

Tests:

Array
var sum = 0; for (var i = 0; i < array.length; i++) { var item = array[i]; sum += item.fn(item.key); }
Object
var sum = 0; var keys = Object.keys(object); for (var i = 0; i < keys.length; i++) { var key = keys[i]; sum += object[key](key); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Array
Object

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

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

LLMs can make mistakes. Check important info.

**Benchmark Explanation**

The provided JSON represents a benchmarking test for JavaScript performance comparison between two approaches: iterating over an array of objects with key-value pairs and iterating over an object with key-value pairs.

**Approaches Compared**

Two main approaches are compared:

1. **Array Approach**: This approach uses an array to store objects, where each object has a `key` property and a `fn` (function) property. The function is called using the `item.fn(item.key)` syntax.
2. **Object Approach**: This approach uses an object with key-value pairs, where each value is another function that takes a `key` parameter.

**Pros and Cons**

### Array Approach

Pros:

* Easier to implement and understand, as it uses a familiar array data structure.
* Might be more intuitive for developers who are used to working with arrays.

Cons:

* May lead to slower performance due to the overhead of pushing elements into an array during each iteration.
* The `fn` function is called using the `item.fn(item.key)` syntax, which can be less readable than calling it directly.

### Object Approach

Pros:

* Can potentially lead to better performance, as lookups in objects are typically faster than searching through arrays.
* Allows for more concise and expressive code, as functions can be defined directly within the object.

Cons:

* May require additional setup or understanding of object notation, which can make it less accessible to some developers.
* The `fn` function is called using the `object[key](key)` syntax, which can also lead to less readable code.

**Library and Functionality**

In the provided benchmark, the library being used is not explicitly mentioned. However, based on the code, it appears that a JavaScript runtime environment is being used, likely with some level of optimization for performance.

The `fn` function in both approaches is simply a placeholder for any arbitrary function that takes a `key` parameter and returns a value. The actual implementation of these functions is not relevant to this benchmark.

**Special JS Features or Syntax**

There are no special JavaScript features or syntax being used in the provided code. It appears to be standard JavaScript, with no experimental or proprietary features.

**Alternatives**

If you're looking for alternatives to measure JavaScript performance, here are a few options:

1. **Benchmark.js**: A popular benchmarking library for Node.js that provides a simple and efficient way to run benchmarks.
2. **JSPerf**: A benchmarking tool specifically designed for JavaScript testing, which allows you to create complex benchmark tests using HTML5 Canvas.
3. **WebPageTest**: A comprehensive web performance testing tool that can measure the performance of your website across various devices and browsers.

Keep in mind that each of these tools has its strengths and weaknesses, and might be better suited for specific use cases or types of benchmarks.

Related benchmarks:

[{key, fn}, ...] vs {[key]: fn, ...} (version: 0)

Iterating over array of {key, fn} vs object of {[key]: fn}

Comparing performance of: Array vs Object

Created: 9 years ago by: Guest

Jump to the latest result

Array

Object

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):