Benchmark: regex replace with and without for (very long text)

Script Preparation code:

var sentence = "Lorem Ipsum is simply dummy text of the printing and typesetting industry.";
var wordList = sentence.split(' ');

var longText = "Lorem Ipsum is simply dummy text of the printing and typesetting industry."

for (let i = 0; i < 10; i += 1) {
  longText = longText + " " + longText
}

Tests:

replace with for
for (let i = 0; i < wordList.length; i += 1) { var re = new RegExp("(" + wordList[i] + ")", "gi"); longText = longText.replace( re, '<span>$1</span>' ); }
replace without for
var re = new RegExp("(" + wordList.join('|') + ")", "gi"); longText = longText.replace( re, '<span>$1</span>' );

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
replace with for
replace without for

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 16_1 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) CriOS/107.0.5304.66 Mobile/15E148 Safari/604.1

Browser/OS: Chrome Mobile iOS 107 on iOS 16.1

View result in a separate tab

Test name	Executions per second
replace with for	12.5 Ops/sec
replace without for	6.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and its various components.

**Benchmark Definition JSON:**

The benchmark definition is a set of instructions that outlines how to prepare the test environment, generate the test data, and run the benchmark. In this case:

* The `Name` and `Description` fields are empty.
* The `Script Preparation Code` section generates a long text by concatenating spaces with itself 10 times, creating a very large string.
* The `Html Preparation Code` section is empty.

**Individual Test Cases:**

The benchmark consists of two individual test cases:

1. "replace with for"
2. "replace without for"

These test cases differ in how they construct the regular expression (regex) to replace words in the long text.

**Options Compared:**

In this benchmark, we have two approaches to replacing words in the long text:

* **Approach 1: Using a `for` loop**
```javascript
for (let i = 0; i < wordList.length; i += 1) {
    var re = new RegExp(\"(\" + wordList[i] + \")\", \"gi\");
    ...
}
```
This approach uses a `for` loop to iterate over the `wordList`, creating a separate regex for each word.

* **Approach 2: Using `|` operator**
```javascript
var re = new RegExp(\"(\" + wordList.join('|') + \")\", \"gi\");
...
```
This approach concatenates all words in `wordList` using the `|` operator to create a single regex pattern.

**Pros and Cons of Each Approach:**

* **Approach 1 (using a `for` loop):**
	+ Pros:
		- Can be more explicit and easier to understand.
		- May be faster due to reduced regex creation overhead.
	+ Cons:
		- More code is generated, which can lead to slower execution times.
		- May result in slower performance due to the additional loop iteration.
* **Approach 2 (using `|` operator):**
	+ Pros:
		- Results in a single regex pattern creation, potentially leading to faster execution times.
		- Can be more concise and easier to read.
	+ Cons:
		- May be less explicit and harder to understand due to the complex regex pattern.
		- Can lead to slower performance if the `|` operator causes additional overhead.

**Library:**

There is no library explicitly mentioned in the benchmark definition. However, it's likely that the `RegExp` class is being used from the built-in JavaScript library (or a polyfill).

**Special JS Features or Syntax:**

None are mentioned in this specific benchmark. If any special features or syntax were present, they would be relevant to understanding and optimizing the code.

**Alternatives:**

Other approaches to replace words in a text could include:

* Using a `set` data structure to eliminate duplicate words
* Using a more efficient algorithm, such as Boyer-Moore or Knuth-Morris-Pratt
* Leveraging native JavaScript features, like `String.prototype.split()` and `String.prototype.replace()`
* Considering a different programming language or framework for optimal performance

Related benchmarks:

regex replace with and without for (very long text) (version: 0)

Comparing performance of: replace with for vs replace without for

Created: 2 years ago by: Registered User

Jump to the latest result

replace with for

replace without for

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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