Benchmark: case insensitive search

Script Preparation code:

var s = "a long string with multiple words"

Tests:

toLowerCase
s.toLowerCase().includes('with')
regexp insensitive
new RegExp('\bwith\b', "i").test(s);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
toLowerCase
regexp insensitive

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 3 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/90.0.4430.212 Safari/537.36

Browser/OS: Chrome 90 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
toLowerCase	8170135.5 Ops/sec
regexp insensitive	2952617.2 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the benchmark and explain what's being tested, compared, and analyzed.

**What is being tested?**

The benchmark tests two approaches to search for a substring in a string:

1. **toLowerCase() method**: This approach converts the entire input string `s` to lowercase using the `toLowerCase()` method.
2. **RegExp with 'i' flag**: This approach uses a regular expression (RegExp) with the 'i' flag to perform case-insensitive matching.

**Options compared**

The benchmark compares two approaches:

1. Using the `toLowerCase()` method
2. Using a RegExp with the 'i' flag

**Pros and Cons of each approach:**

**toLowerCase() method:**

Pros:

* Simple and straightforward implementation
* Fast for small to medium-sized strings

Cons:

* Requires converting the entire input string, which can be slow for large strings
* May not be as efficient as RegExp for case-insensitive matching

**RegExp with 'i' flag:**

Pros:

* Can perform case-insensitive matching without modifying the original input string
* More efficient than `toLowerCase()` for large strings or multiple searches

Cons:

* Requires more complex implementation (creating a RegExp object and specifying flags)
* May be slower than `toLowerCase()` for small to medium-sized strings

**Other considerations:**

* **String normalization**: The benchmark does not consider the impact of string normalization on the performance of these approaches. Normalization can affect the length and structure of strings, which may impact the performance of the search algorithms.
* **Input data distribution**: The benchmark assumes a uniform distribution of input data, but in reality, the input data may follow different distributions (e.g., skewed or bimodal).
* **Browser variations**: The benchmark only considers one browser version (Chrome 90). In practice, there may be other browsers with different performance characteristics for these approaches.

**Library used:**

The `toLowerCase()` method and RegExp with 'i' flag both use the built-in JavaScript standard library functions. No external libraries are required.

**Special JS features or syntax:**

This benchmark does not use any special JS features or syntax. It only uses standard JavaScript language constructs.

**Benchmark preparation code:**

The script preparation code is a simple string `s = "a long string with multiple words"`. This string is used to test the search algorithms.

Overall, this benchmark provides a good starting point for comparing the performance of two approaches to case-insensitive searching in JavaScript. However, it has some limitations and could be improved by considering additional factors, such as input data distribution and browser variations.

Related benchmarks:

case insensitive search (version: 0)

Comparing performance of: toLowerCase vs regexp insensitive

Created: 3 years ago by: Guest

Jump to the latest result

toLowerCase

regexp insensitive

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):