Benchmark: parseInt vs ~~ - MeasureThat.net

HTML Preparation code:

<div id=''></div>

Script Preparation code:

var baseStr = '23';

Tests:

parserInt
const a = parseInt(baseStr)
~~
const b = ~~(baseStr)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
parserInt
~~

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

This benchmark does not have any results yet. Be the first one to run it!

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

LLMs can make mistakes. Check important info.

Let's dive into explaining the provided JSON and benchmark.

**Benchmark Overview**

The provided JSON represents a JavaScript microbenchmark test case, specifically comparing two approaches to convert a string to an integer: `parseInt()` and the bitwise NOT operator (`~~`).

**Options Compared**

The benchmark compares the execution time of:

1. `parseInt(baseStr)`: Uses the built-in `parseInt()` function to convert the string `baseStr` to an integer.
2. `~~(baseStr)`: Uses the bitwise NOT operator (`~~`) to perform a negative integer arithmetic operation, effectively converting the string to an integer.

**Pros and Cons of Each Approach**

1. `parseInt(baseStr)`:
	* Pros: Widely supported and well-documented, performs integer conversion correctly.
	* Cons: Can be slower than the bitwise NOT approach due to the overhead of function calls and type conversions.
2. `~~(baseStr)`: 
	* Pros: Faster and more lightweight compared to `parseInt()`, as it leverages bitwise operations.
	* Cons: May not work correctly for non-numeric input strings, and its behavior can be counterintuitive due to the use of negative integer arithmetic.

**Library and Special JS Feature**

There is no specific library used in this benchmark. However, note that the `~~` operator relies on a special JavaScript feature called "bitwise NOT with unboxed numeric arguments" (ECMAScript 2015+), which allows the bitwise NOT operator to operate on numbers directly without first converting them to integers.

**Benchmark Preparation Code**

The script preparation code creates a variable `baseStr` and assigns it the string value `'23'`.

**Individual Test Cases**

Each test case is defined by a "Benchmark Definition" that specifies how to run the test. In this case, there are two test cases:

1. `"const a = parseInt(baseStr");`: Runs the code snippet inside the `parseInt()` function.
2. `"const b = ~~(baseStr);"`: Runs the code snippet inside the bitwise NOT operator (`~~`) with the string as an argument.

**Benchmark Result**

The latest benchmark result shows that:

* The `~~` approach executed approximately 33 times faster than the `parseInt()` approach, with a raw execution time of around 24544528.0 executions per second.
* Both tests were run on Chrome 104 browser on a desktop device with Mac OS X 10.15.7 operating system.

**Other Alternatives**

If you're interested in exploring other alternatives for integer conversion, consider using:

1. `Number()` function: Similar to `parseInt()`, but can convert strings to floating-point numbers if possible.
2. `atob()` and `decodeURIComponent()` functions: Can be used to convert a string to an unsigned 32-bit integer, but might not provide accurate results for negative integers.

For more advanced or performance-critical scenarios, you may want to explore other libraries like Fast.js, which provides optimized integer conversion methods.

Related benchmarks:

parseInt vs ~~ (version: 0)

Comparing performance of: parserInt vs ~~

Created: 3 years ago by: Guest

Jump to the latest result

parserInt

~~

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):