Benchmark: charcodeat vs. codepointat

Script Preparation code:

var str = "\x02idjghjhdfjfdjfdjhgkghkghk dhfdg dhdf dfhdfh"

Tests:

codepointat tostring
str.codePointAt(0).toString()
charcodeat tostring
str.charCodeAt(0).toString()
codepointat
str.codePointAt(0)
charcodeat
str.charCodeAt(0)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
codepointat tostring
charcodeat tostring
codepointat
charcodeat

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 10 months ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:124.0) Gecko/20100101 Firefox/124.0

Browser/OS: Firefox 124 on Windows

View result in a separate tab

Test name	Executions per second
codepointat tostring	995715712.0 Ops/sec
charcodeat tostring	996086784.0 Ops/sec
codepointat	1002618304.0 Ops/sec
charcodeat	958257408.0 Ops/sec

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

LLMs can make mistakes. Check important info.

**What is being tested?**

The provided JSON represents a JavaScript microbenchmark test case on MeasureThat.net. The benchmark tests the performance of two different ways to access and convert Unicode code points in a string:

1. `codePointAt` method: This method returns the code point at a specific index in the string, without converting it to a character.
2. `charCodeAt` method with `toString`: This method returns the ASCII value of the character at a specific index in the string, and then converts this value to a string using the `toString()` method.

**Options compared**

The benchmark compares the performance of these two approaches:

* `codePointAt`
* `charCodeAt` followed by `toString`

**Pros and cons of each approach:**

1. **`codePointAt`**:
	* Pros:
		+ More efficient, as it only needs to access a single code point.
		+ Less overhead compared to the `charCodeAt`-`toString` combination.
	* Cons:
		+ Requires the string to be in surrogate pairs (UTF-16), which can lead to slower performance on some platforms.
2. **`charCodeAt` followed by `toString`**:
	* Pros:
		+ Works regardless of the presence of surrogate pairs or non-BMP characters.
	* Cons:
		+ Requires an extra operation (`toString()` conversion), which incurs additional overhead.

**Library and its purpose**

None of the provided benchmark definitions use any external libraries. However, it's worth noting that some browsers may have internal optimizations or caching mechanisms that could affect performance.

**Special JavaScript features or syntax**

The benchmark defines several test cases using special JavaScript features:

* `codePointAt` method (introduced in ECMAScript 2019)
* `charCodeAt` method with `toString` conversion
* Unicode escape sequences (`\x02`, `\u{...}`) for creating surrogate pairs

These features are designed to take advantage of specific browser optimizations or caching mechanisms. The benchmark is likely run on multiple browsers, including Firefox 124, which supports these features.

**Other alternatives**

If you want to compare performance with other approaches, consider the following:

* Using a different method to access code points, such as `String.codePointAt()` (which was introduced in ECMAScript 2019 and is similar to `codePointAt` but uses a more efficient algorithm)
* Using a library or utility function to perform the conversion, such as Unicode normalization functions
* Comparing performance with different string encoding schemes, such as UTF-8 or UTF-16

Related benchmarks:

charcodeat vs. codepointat (version: 0)

Comparing performance of: codepointat tostring vs charcodeat tostring vs codepointat vs charcodeat

Created: 3 years ago by: Guest

Jump to the latest result

codepointat tostring

charcodeat tostring

codepointat

charcodeat

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):