Benchmark: Comparing performance of native type comparation and Lodash

HTML Preparation code:


<script src='https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.min.js'></script>

Script Preparation code:

var a = function () {};
var b = undefined;

Tests:

Lodash for valid case
_.isFunction(a)
Native for valid case using instanceof
a instanceof Function
Native for valid case using typeof
typeof a === 'function'
Lodash for invalid case
_.isFunction(b)
Native for invalid case using instanceof
b instanceof Function
Native for invalid case using typeof
typeof b === 'function'

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Lodash for valid case
Native for valid case using instanceof
Native for valid case using typeof
Lodash for invalid case
Native for invalid case using instanceof
Native for invalid case using typeof

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):

LLMs can make mistakes. Check important info.

Let's break down the benchmark test and its components.

**Benchmark Overview**

The benchmark is designed to compare the performance of two approaches to check if an object or variable is a function in JavaScript:

1. Using the `_.isFunction()` method from Lodash (a popular utility library).
2. Using the `instanceof` operator directly on the variable.
3. Using the `typeof` operator with the `'function'` string literal.

**Options Compared**

The benchmark compares the performance of these three approaches for two cases:

* Valid case: `var a = function () {};`
* Invalid case: `var b = undefined;`

In each case, the benchmark measures the execution speed of each approach on different browsers and devices.

**Pros and Cons of Each Approach**

1. **Lodash's _.isFunction()**
	* Pros:
		+ Easy to use and understand.
		+ Well-maintained and widely adopted.
	* Cons:
		+ May introduce additional overhead due to the library's complexity.
2. **instanceof operator**
	* Pros:
		+ Fast and efficient, as it checks the prototype chain of an object.
		+ Only requires JavaScript itself, no external libraries.
	* Cons:
		+ Can be less intuitive for developers who are not familiar with its usage.
3. **typeof operator with `'function'` string literal**
	* Pros:
		+ Fast and efficient, similar to `instanceof`.
		+ Can be used in a more straightforward way than `_.isFunction()`.
	* Cons:
		+ May not work correctly for certain types of functions (e.g., those returned by `Function()`).

**Library: Lodash**

Lodash is a popular JavaScript utility library that provides a wide range of functions for tasks such as array manipulation, string manipulation, and more. In this benchmark, the `_isFunction()` method from Lodash is used to check if an object or variable is a function.

**Special JS Features/Syntax**

None mentioned in the provided code snippet. However, it's worth noting that some JavaScript features like arrow functions, generators, and async/await may affect performance when using these approaches.

**Other Alternatives**

If you need to compare the performance of different approaches to check if an object or variable is a function, you might also consider:

* Using `Type` (formerly known as `typeof`) with a more specific type (e.g., `function`)
* Implementing your own custom implementation using `Object.prototype.toString()` and some basic string manipulation
* Using other libraries like Fastify, which provides a built-in `isFunction()` method.

Keep in mind that these alternatives might not be directly comparable to the Lodash approach or the `instanceof` operator, as they may have different performance characteristics.

Latest run results:

Run details: (Test run date: 5 years ago)

User agent: Mozilla/5.0 (Android 9; Tablet; rv:66.0) Gecko/66.0 Firefox/66.0

Browser/OS: Firefox 66 on Android

View result in a separate tab

Test name	Executions per second
Lodash for valid case	13602124.0 Ops/sec
Native for valid case using instanceof	37559788.0 Ops/sec
Native for valid case using typeof	98991664.0 Ops/sec
Lodash for invalid case	27980756.0 Ops/sec
Native for invalid case using instanceof	40063572.0 Ops/sec
Native for invalid case using typeof	121919288.0 Ops/sec

Related benchmarks:

Comparing performance of native type comparation and Lodash (version: 0)

Comparing performance of: Lodash for valid case vs Native for valid case using instanceof vs Native for valid case using typeof vs Lodash for invalid case vs Native for invalid case using instanceof vs Native for invalid case using typeof

Created: 5 years ago by: Registered User

Jump to the latest result

Lodash for valid case

Native for valid case using instanceof

Native for valid case using typeof

Lodash for invalid case

Native for invalid case using instanceof

Native for invalid case using typeof

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):