Benchmark: Filtering La - MeasureThat.net

Script Preparation code:

var list = [...Array(10000000).keys()].map((index) => `ITEM_${index}`);
var val = 'ITEM_100';

Tests:

Regex case
const trimVal = val.trim(); const regex = new RegExp(`^${trimVal}`, 'i'); const x = list.filter((item) => { return trimVal !== '' ? regex.test(item) : true; });
Indexof no trime, begins with
const lowerVal = val.toLowerCase(); const x = list.filter((item) => { return val !== '' ? item.toLowerCase().indexOf(lowerVal) === 0: true; });
Indexof trim, begins with
const trimVal = val.trim().toLowerCase(); const x = list.filter((item) => { return trimVal !== '' ? item.toLowerCase().indexOf(trimVal) === 0 : true; });

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Regex case
Indexof no trime, begins with
Indexof trim, begins with

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.

Let's break down the provided benchmark and its test cases.

**What is being tested?**

The benchmark tests the performance of filtering an array using different approaches:

1. `Regex case`: This approach uses regular expressions to filter the array. The regular expression engine will be used to search for a specific value in each element of the array.
2. `Indexof no trime, begins with`: This approach uses the `indexOf()` method to find the index of a value in the array, and then checks if that index is greater than 0 (i.e., the value starts with the target string). If it does, the element is included in the result.
3. `Indexof trim, begins with`: Similar to the previous approach, but it trims the target value before searching for its index.

**Options compared**

The three approaches differ in how they search for the target value:

1. **Regex case**: Uses a regular expression engine to search for the exact value.
2. **Indexof no trime, begins with**: Uses `indexOf()` to find the starting position of the target value, and then checks if that position is greater than 0.
3. **Indexof trim, begins with**: Similar to the previous approach, but trims the target value before searching for its index.

**Pros and Cons**

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

1. **Regex case**:
	* Pros: Can be powerful for matching complex patterns, flexible, and efficient.
	* Cons: May be slower due to the overhead of regular expression compilation and execution.
2. **Indexof no trime, begins with**:
	* Pros: Simple, straightforward, and likely to be faster than the regex case due to the optimized `indexOf()` implementation.
	* Cons: Requires an exact match (starts with), which may not cover all scenarios.
3. **Indexof trim, begins with**:
	* Pros: Similar to the previous approach, but trims the target value before searching, making it more flexible.
	* Cons: May be slower due to the additional trimming operation.

**Library/Functions used**

None of the test cases rely on external libraries or functions beyond what's built into JavaScript.

**Special JS features/syntax**

There are no special JavaScript features or syntax used in these benchmark cases. However, it's worth noting that some older browsers may not support regular expressions (Regex case) due to compatibility issues.

**Other alternatives**

If you wanted to test other approaches, here are a few examples:

1. **Array.prototype.includes()**: Instead of using `indexOf()` and checking the result, you could use the more modern `includes()` method, which is available in ECMAScript 2015 (ES6) and later.
2. **For loop with index checking**: You could write a simple for loop that iterates over each element in the array and checks if it matches the target value using conditional statements.

Keep in mind that these alternative approaches may not be as efficient or straightforward to implement as the original test cases, but they can provide additional insights into performance optimization strategies.

Related benchmarks:

Filtering La (version: 0)

Comparing performance of: Regex case vs Indexof no trime, begins with vs Indexof trim, begins with

Created: 4 years ago by: Guest

Jump to the latest result

Regex case

Indexof no trime, begins with

Indexof trim, begins with

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):