Benchmark: localeCompare vs charCodeAt

Script Preparation code:

function localeCompare(a, b) {
    return a.localeCompare(b);
}

function compare(a, b) {
    const aLength = a.length;
    const bLength = b.length;
    for (let i = 0; i < bLength; ++i) {
        let code = a.charCodeAt(i);
        if (isNaN(code)) {
            // b startsWith a
            return -1;
        }
        code -= b.charCodeAt(i);
        if (code)
            return code;
    }
    // a startsWith b
    return aLength > bLength ? 1 : 0;
}

Tests:

localeCompare
localeCompare("radiogQe8_7yhdY4Cl1QQSAsEJocXvTjlCzDN", "radioradioAu5NNprfgPH94MDcxL-rElEcHDvmG");
compare
compare("radiogQe8_7yhdY4Cl1QQSAsEJocXvTjlCzDN", "radioradioAu5NNprfgPH94MDcxL-rElEcHDvmG");

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
localeCompare
compare

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/132.0.0.0 Safari/537.36

Browser/OS: Chrome 132 on Linux

View result in a separate tab

Test name	Executions per second
localeCompare	50835976.0 Ops/sec
compare	51049480.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and its various components.

**Benchmark Definition JSON**

The provided JSON defines two JavaScript microbenchmarks: `localeCompare` and `compare`. Both benchmarks compare two Unicode strings, but they use different approaches to do so.

*   The **`localeCompare`** function is part of the ECMAScript standard and is used for comparing strings in a culturally aware manner. It takes into account factors like language, region, and locale.
*   The `compare` function is a custom implementation that compares two Unicode strings by iterating through them character by character and subtracting the ASCII values (using `charCodeAt`) of corresponding characters.

**Options Compared**

The benchmark compares two options:

1.  **`localeCompare`**: Uses the built-in JavaScript `localeCompare` method for string comparison, taking into account cultural awareness.
2.  **`compare`**: Implements a custom comparison function that manually iterates through the strings using ASCII values (using `charCodeAt`) to compare characters.

**Pros and Cons**

Here are some pros and cons of each approach:

*   **`localeCompare`**:
    *   Pros:
        +   Culturally aware, taking into account factors like language, region, and locale.
        +   Typically faster than manual ASCII-based comparison (since it's a built-in method).
    *   Cons:
        +   May have performance issues in certain cases due to its complexity.
        +   May not be suitable for simple string comparisons where cultural awareness is unnecessary.

*   **`compare`**:
    *   Pros:
        +   Typically faster than `localeCompare` (since it's a custom implementation).
        +   Suitable for simple string comparisons where cultural awareness is unnecessary.
    *   Cons:
        +   Does not account for cultural differences in string comparison.
        +   Requires manual maintenance to ensure accuracy and performance.

**Library Used**

The `compare` function uses the `charCodeAt` method, which is a built-in JavaScript method that returns an integer representing the Unicode code point at a specified index of a string. This method is used to compare characters by subtracting their ASCII values.

**Special JS Feature/Syntax**

There are no special JavaScript features or syntaxes mentioned in this benchmark. It's purely focused on comparing strings using different approaches.

**Other Alternatives**

Other alternatives for string comparison include:

*   Using the `String.prototype.localeCompare()` method (available in modern browsers) which provides a similar functionality to `localeCompare()`.
*   Implementing a custom comparison function like `compare` but with support for Unicode normalization and other advanced features.
*   Using third-party libraries or modules that provide optimized string comparison algorithms.

These alternatives may offer better performance, accuracy, or feature sets depending on the specific use case.

Related benchmarks:

localeCompare vs charCodeAt (version: 0)

localeCompare vs charCodeAt

Comparing performance of: localeCompare vs compare

Created: 4 years ago by: Registered User

Jump to the latest result

localeCompare

compare

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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