Benchmark: jQuery .first() vs :first vs .filter(:first) vs .eq(0) vs $(.get(0)) vs $([0]) vs :eq(0)

HTML Preparation code:

<div class="container">
  <div class="inner"></div>
  <div class="inner"></div>
  <div class="inner"></div>
  <div class="inner"></div>
  <div class="inner"></div>
</div>

Tests:

.first()
$('.container .inner').first();
:first
$('.container .inner:first');
.filter(:first)
$('.container .inner').filter(':first');
.eq(0)
$('.container .inner').eq(0);
$(.get(0))
$($('.container .inner').get(0));
$([0])
$($('.container .inner')[0]);
:eq(0)
$('.container .inner:eq(0)');

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
.first()
:first
.filter(:first)
.eq(0)
$(.get(0))
$([0])
:eq(0)

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 28 days ago):

LLMs can make mistakes. Check important info.

I'll break down the benchmark and explain what's being tested, compared, and the pros and cons of each approach.

**Benchmark Definition**

The benchmark tests various methods for selecting the first element from a jQuery object or array. The test cases are:

1. `$.first()`
2. `:first` (using the `:first` pseudo-class)
3. `.filter(':first')`
4. `.eq(0)`
5. `$(.get(0))`
6. `$([0])`
7. `:eq(0)`

**Library and Purpose**

* jQuery is a popular JavaScript library for DOM manipulation and event handling.
* `.first()` and `.eq(0)` are methods that select the first element in the jQuery object.
* `:first` and `:eq(0)` are pseudo-classes (not actual methods) that select the first element using CSS selectors.

**Test Cases**

Each test case measures the execution time of a specific method. Here's what's being tested:

1. `$.first()`: Measures the execution time of the `.first()` method, which returns an array-like object containing one element.
2. `:first`: Measures the execution time of the `:first` pseudo-class, which uses CSS selectors to select the first element.
3. `.filter(':first')`: Measures the execution time of using the `.filter()` method with the `:first` pseudo-class, which filters the elements based on the pseudo-class.
4. `.eq(0)`: Measures the execution time of the `.eq(0)` method, which sets the value of an element to zero and returns an array-like object containing one element.
5. `$(.get(0))`: Measures the execution time of the `$()` function with `$(.get(0))`, which attempts to access the first DOM element using the `get(0)` property.
6. `$([0])`: Measures the execution time of the `$()` function with `$([0])`, which attempts to access an array element at index 0.
7. `:eq(0)`: Measures the execution time of the `:eq(0)` pseudo-class, which uses CSS selectors to select the first element.

**Pros and Cons**

Here's a brief summary of the pros and cons for each approach:

1. `.first()`:
	* Pros: Simple, efficient, and well-supported by jQuery.
	* Cons: May not be as flexible as other methods (e.g., using pseudo-classes).
2. `:first`:
	* Pros: More flexible than `.first()`, allows for CSS selectors.
	* Cons: May be slower due to the overhead of parsing CSS selectors.
3. `.filter(':first')`:
	* Pros: Allows for filtering elements based on the `:first` pseudo-class.
	* Cons: May be slower than other methods, as it involves filtering the entire set of elements.
4. `.eq(0)`:
	* Pros: Simple and efficient, well-supported by jQuery.
	* Cons: Limited to setting an element's value to zero.
5. `$(.get(0))`:
	* Pros: None notable.
	* Cons: May be slower due to the overhead of accessing DOM elements using `get(0)`.
6. `$([0])`:
	* Pros: None notable.
	* Cons: May be slower due to the overhead of accessing array elements.
7. `:eq(0)`:
	* Pros: More flexible than `.eq(0)`, allows for CSS selectors.
	* Cons: May be slower due to the overhead of parsing CSS selectors.

**Other Alternatives**

Some alternative methods that could be tested include:

1. Using `Array.prototype.shift()` or `Array.prototype.pop()` to remove and return the first element from an array-like object.
2. Using a custom function with a dynamic selector (e.g., `function getFirstElement(selector) { ... }`).
3. Using other pseudo-classes, such as `:last()`, `:before()`, or `:after()`.

These alternative methods could provide additional insights into the performance characteristics of each approach.

Latest run results:

Run details: (Test run date: 2025 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/65.0.3325.181 Safari/537.36

Browser/OS: Chrome 65 on Windows

View result in a separate tab

Test name	Executions per second
.first()	61157.2 Ops/sec
:first	41783.9 Ops/sec
.filter(:first)	35651.9 Ops/sec
.eq(0)	57153.0 Ops/sec
$(.get(0))	49856.6 Ops/sec
$([0])	55035.2 Ops/sec
:eq(0)	43791.0 Ops/sec

Related benchmarks:

jQuery .first() vs :first vs .filter(:first) vs .eq(0) vs $(.get(0)) vs $([0]) vs :eq(0) (version: 0)

Comparing performance of: .first() vs :first vs .filter(:first) vs .eq(0) vs $(.get(0)) vs $([0]) vs :eq(0)

Created: 6 years ago by: Guest

Jump to the latest result

.first()

:first

.filter(:first)

.eq(0)

$(.get(0))

$([0])

:eq(0)

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 28 days ago):