Benchmark: while and replace vs split and join

Script Preparation code:

var myList = [
  "aglio_e_olio",
  "breakfast_with_crushed_avocado_and_fried_eggs",
  "chicken_rice", "classic_smash_burger",
  "french_omelette",
  "french_toast",
  "philly_cheesesteak",
  "shrimp_fried_rice",
  "spaghetti_in_tomato_sauce"
];

Tests:

while and replace
for (let i of myList) { let temp = i; while (temp.indexOf("+") != -1) { temp = temp.replace("+", " "); } }
split and join
for (let i of myList) { let temp = i.split("_").join(" ").toUpperCase(); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
while and replace
split and join

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/92.0.4515.107 Safari/537.36

Browser/OS: Chrome 92 on Windows

View result in a separate tab

Test name	Executions per second
while and replace	1910783.1 Ops/sec
split and join	204288.0 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 provided benchmark JSON and explain what is being tested, compared options, pros and cons of each approach, and other considerations.

**Benchmark Overview**

MeasureThat.net is a website that allows users to create and run JavaScript microbenchmarks. The benchmark in question tests two approaches for replacing a specific character (+) in a string: using a `while` loop with `replace()` method or using the `split()` and `join()` methods.

**Script Preparation Code**

The script preparation code defines an array of strings, `myList`, which contains several food-related names. This array will be used as input for the benchmark test cases.

```javascript
var myList = [
  "aglio_e_olio",
  "breakfast_with_crushed_avocado_and_fried_eggs",
  "chicken_rice",
  "classic_smash_burger",
  "french_omelette",
  "french_toast",
  "philly_cheesesteak",
  "shrimp_fried_rice",
  "spaghetti_in_tomato_sauce"
];
```

**Html Preparation Code**

There is no HTML preparation code provided, which means the benchmark tests will only focus on JavaScript execution performance.

**Individual Test Cases**

The benchmark consists of two test cases:

1. **while and replace**
```javascript
for (let i of myList) {
  let temp = i;
  while (temp.indexOf("+") != -1) {
    temp = temp.replace("+", " ");
  }
}
```

This test case uses a `while` loop to iterate over the input string, replacing each occurrence of the character "+" with a space.

2. **split and join**
```javascript
for (let i of myList) {
  let temp = i.split("_").join(" ").toUpperCase();
}
```

This test case uses the `split()` method to split the input string into substrings separated by "_" and then joins them back together with spaces using the `join()` method, followed by converting the resulting string to uppercase.

**Library Used**

The `split()` and `join()` methods are part of the JavaScript String prototype. These methods are used extensively in modern web development for manipulating strings.

**Pros and Cons of Each Approach**

1. **while and replace**
	* Pros:
		+ More concise and readable code
		+ Avoids creating intermediate arrays or objects
	* Cons:
		+ May be slower due to the overhead of regular expressions (although it's unlikely to make a significant difference)
2. **split and join**
	* Pros:
		+ Can be faster for large input strings, as it avoids the overhead of regular expressions
	* Cons:
		+ More verbose code compared to the `while` loop approach

**Other Considerations**

When evaluating performance, consider the following:

* The size of the input string: Larger inputs may favor one approach over the other due to caching and memory allocation.
* The frequency of occurrence of the character to be replaced (+ in this case): If the character occurs infrequently, the `while` loop approach might be more efficient.

**Alternatives**

Other approaches for replacing a character in a string could include:

1. Using a regular expression with the `replace()` method (e.g., `str.replace(/\+/g, " ")`)
2. Using the `replaceAll()` method (if supported by the browser)
3. Creating an array of replacements and applying it using a loop or `forEach()`

However, these alternatives may incur additional overhead due to regular expressions, string manipulation, or array creation, which could impact performance.

Keep in mind that the actual performance difference between these approaches will depend on the specific use case and input size.

Related benchmarks:

while and replace vs split and join (version: 0)

testing some codes

Comparing performance of: while and replace vs split and join

Created: 3 years ago by: Guest

Jump to the latest result

while and replace

split and join

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):