Benchmark: replace vs substring vs split

Script Preparation code:

var strIn = 'thisisatest-123456';
var strOut = '';

Tests:

substring
strOut = strIn.substring(12);
replace inline
strOut = strIn.replace('thisisatest-', "");
split
strOut = strIn.split('-')[0];

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
substring
replace inline
split

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks on MeasureThat.net.

**Benchmark Definition**

The benchmark is designed to compare three different approaches for replacing or extracting a substring from a string: `substring`, `replace inline`, and `split`. The benchmark uses a simple input string `"thisisatest-123456"` and produces an empty string as output.

**Options Compared**

*   **Substring**: Uses the `substring` method, which returns a subset of characters in a string.
*   **Replace Inline**: Uses the `replace` method with an inline replacement pattern, where only the first occurrence is replaced.
*   **Split**: Uses the `split` method to split the input string into substrings using a separator.

**Pros and Cons**

*   **Substring**:
    *   Pros: Simple and efficient for finding a specific substring. It's widely supported across browsers and platforms.
    *   Cons: May not be suitable for large strings or complex search patterns due to its simple implementation.
*   **Replace Inline**:
    *   Pros: Suitable for replacing a specific pattern in a string, especially when only the first occurrence needs to be replaced.
    *   Cons: Can be less efficient than other methods, especially for larger strings or more complex replacements. Also, it may not work as expected with regular expressions.
*   **Split**:
    *   Pros: Suitable for splitting a string into substrings using a separator. It's widely supported and can handle large inputs efficiently.
    *   Cons: Requires specifying the separator, which might not always be desirable.

**Library Usage**

None of these methods rely on external libraries; they are built-in JavaScript functions or methods.

**Special JS Features/Syntax**

There is no special JavaScript feature or syntax used in this benchmark. The methods compare are simple and widely supported across browsers and platforms.

**Alternative Approaches**

For replacing substrings, you might consider using regular expressions (e.g., `strIn.replace(/pattern/g, replacement)`) for more complex patterns or replacing only the first occurrence. For splitting strings, you can use `Array.prototype.map()` to split a string into an array of substrings.

Here's some sample code demonstrating these alternative approaches:

```javascript
// Using regular expressions
function replaceRegex(strIn, strOut) {
    return strIn.replace(/thisisatest/g, '');
}

// Replacing only the first occurrence
function replaceFirst(strIn, strOut) {
    return strIn.replace('thisisatest-', '');
}

// Splitting a string into an array of substrings
function splitArray(strIn) {
    return strIn.split('-');
}
```

These alternative approaches can offer more flexibility and control over the replacement or splitting process, but may also have performance implications depending on the input data.

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/112.0.0.0 Safari/537.36

Browser/OS: Chrome 112 on Windows

View result in a separate tab

Test name	Executions per second
substring	5248685.0 Ops/sec
replace inline	3638704.8 Ops/sec
split	3021979.5 Ops/sec

Related benchmarks:

replace vs substring vs split (version: 0)

Comparing performance of: substring vs replace inline vs split

Created: one year ago by: Guest

Jump to the latest result

substring

replace inline

split

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):