Benchmark: padStart vs while loop

Tests:

1
let stringValue = "9"; let zeroCount = 4 - stringValue.length; while (zeroCount-- > 0) { stringValue = '0' + stringValue; }
2
let stringValue = "9"; let zeroCount = 4 - stringValue.length; stringValue.padStart(4, "0");

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
1
2

Fastest: N/A

Slowest: N/A

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/134.0.0.0 Safari/537.36

Browser/OS: Chrome 134 on Windows

View result in a separate tab

Test name	Executions per second
1	55965204.0 Ops/sec
2	43846820.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down what's being tested in this benchmark.

**Benchmark Goal**
The goal of this benchmark is to compare the performance of two approaches to pad a string with leading zeros: using a `while` loop and using the `padStart()` method.

**Options Compared**

1. **While Loop**: This approach uses a traditional `while` loop to repeatedly append a zero to the end of the string.
2. **padStart() Method**: This approach uses the built-in `padStart()` method, which pads a string with leading zeros based on a specified length.

**Pros and Cons**

**While Loop:**

Pros:

* Can be more flexible, as it allows for manual control over the loop iterations.
* May be faster for very short strings or specific use cases where precision is crucial.

Cons:

* Can be slower than the `padStart()` method due to the overhead of explicit loop control.
* Requires more code and maintenance effort compared to the `padStart()` method.

**padStart() Method:**

Pros:

* Fast and efficient, as it's a built-in method optimized for performance.
* Concise and easy to read, with fewer lines of code.
* Less prone to errors due to its standardized syntax.

Cons:

* May not be suitable for very short strings or specific use cases where precision is crucial.
* Limited control over the padding process, which might be a concern in certain scenarios.

**Library Used**
In this benchmark, there isn't an explicit library mentioned. However, if we assume that the `padStart()` method relies on the browser's built-in string manipulation functionality, it can be argued that the JavaScript Engine or Virtual Machine (VM) is playing a crucial role in executing this code.

**Special JS Feature/Syntax**
There are no specific JavaScript features or syntax used beyond the standard language. However, keep in mind that some browsers might have quirks or optimizations for certain string manipulation methods.

**Other Alternatives**

For similar benchmarks, you could explore other string padding techniques, such as:

* Using the `toString()` method with a leading zero
* Employing regular expressions (e.g., `^0{4}`) to pad the string
* Utilizing a custom function or library specifically designed for string manipulation

Keep in mind that each approach has its own trade-offs and might be more suitable for certain use cases. The choice ultimately depends on performance requirements, maintainability concerns, and personal preference.

If you'd like to explore these alternatives, feel free to ask, and I can provide further explanations and insights!

Related benchmarks:

padStart vs while loop (version: 0)

Comparing performance of: 1 vs 2

Created: one year ago by: Guest

Jump to the latest result

1

2

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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