Benchmark: Spilt() vs Substring()

Script Preparation code:

var paragraph = 'Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Morbi enim nunc faucibus a pellentesque sit amet porttitor. Hac habitasse platea dictumst quisque sagittis purus sit amet volutpat. Viverra accumsan in nisl nisi scelerisque eu. Massa tincidunt dui ut ornare lectus sit amet est. Nec nam aliquam sem et tortor consequat id porta. Ut eu sem integer vitae justo eget. Quam vulputate dignissim suspendisse in est ante in nibh. A scelerisque purus semper eget duis. Non pulvinar neque laoreet suspendisse interdum consectetur.';

Tests:

split()
var split = paragraph.split(' '); console.log(split[split.length - 1]);
substring()
console.log(paragraph.substring(paragraph.lastIndexOf(' ') + 1))

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
split()
substring()

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 15_1_1 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/15.1 Mobile/15E148 Safari/604.1

Browser/OS: Mobile Safari 15 on iOS 15.1.1

View result in a separate tab

Test name	Executions per second
split()	469608.2 Ops/sec
substring()	1401532.8 Ops/sec

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

LLMs can make mistakes. Check important info.

I'll break down the provided benchmark and explain what's being tested, compared, and their pros/cons.

**Benchmark Definition**

The benchmark is designed to compare the performance of two string splitting methods in JavaScript: `split()` and `substring()`.

**Test Cases**

There are two test cases:

1. **`split()`**: This test case uses the `split()` method to split a given paragraph into an array of words. The last word of the array is then logged to the console.
2. **`substring()`**: This test case uses the `substring()` method to extract the last word from the original paragraph. The extracted substring is then logged to the console.

**Libraries and Special Features**

None, as both methods are native JavaScript functions.

**Comparison**

The benchmark compares the performance of these two methods on a given string. The main difference between them lies in how they handle edge cases:

* `split()`:
	+ Splits the string into an array of words.
	+ Returns an array with the last word at index `length - 1`.
	+ Can be slower for shorter strings due to the overhead of creating an array.
* `substring()`: 
	+ Extracts a substring starting from a specified position and length.
	+ Can be faster for shorter strings since it only requires calculating the start and end indices.

**Pros/Cons**

Pros:

* `split()`:
	+ Handles edge cases more robustly (e.g., empty strings, null/undefined inputs).
	+ Often preferred for its simplicity and readability.
* `substring()`: 
	+ Can be faster for shorter strings due to reduced overhead.
	+ Can lead to slower performance for longer strings if not used carefully.

Cons:

* `split()`:
	+ May be slower for very short strings due to array creation.
	+ Returns an array, which can consume more memory.
* `substring()`: 
	+ Can be error-prone if not used correctly (e.g., incorrect start or end indices).
	+ Requires manual indexing calculations.

**Other Alternatives**

Other string splitting methods in JavaScript include:

1. `indexOf()` and slicing: This approach involves finding the last occurrence of a space character using `indexOf()`, then extracting the substring from that index to the end of the string.
2. Regular expressions: Using regular expressions can provide more flexibility, but may also introduce additional overhead.

In general, for simple use cases, `split()` is often preferred due to its simplicity and readability. However, if performance is critical, using `substring()` with careful indexing calculations might be a better option.

Related benchmarks:

Spilt() vs Substring() (version: 0)

Comparing performance of: split() vs substring()

Created: 2 years ago by: Guest

Jump to the latest result

split()

substring()

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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