Benchmark: manual vs filter 2

Script Preparation code:

function classnames2(a, b) {
    return a ? (b ? `${a} ${b}` : a) : b || '';
}

function classnames3(a, b, c) {
    return a
        ? b
            ? c
                ? `${a} ${b} ${c}`
                : `${a} ${b}`
            : c
            ? `${a} ${c}`
            : a
        : classnames2(b, c);
}

function classnames2b(a, b) {
    return a ? (b ? a + " " + b : a) : b || '';
}

function classnames3b(a, b, c) {
    return a
        ? b
            ? c
                ? a + " " + b + " " + c
                : a + " " + b
            : c
            ? a + " " + c
            : a
        : classnames2b(b, c);
}

function classnamesFlex(...classes) {
    return classes.filter(Boolean).join(' ');
}

function classnamesFlex2() {
    return [].filter.call(arguments, function(v) {return !!v;}).join(' ');
}

// explicitly handling 2 arguments handles most of our use cases efficiently
function classnames(a, b, c) {
    const numArgs = arguments.length;

    if (numArgs === 1) {
        return a || '';
    } else if (numArgs === 2) {
        return classnames2(a, b);
    } else if (numArgs === 3) {
        return classnames3(a, b, c);
    } else {
        return classnamesFlex.apply(null, arguments);
    }
}

function classnames2(a, b, c) {
    const numArgs = arguments.length;

    if (numArgs === 1) {
        return a || '';
    } else if (numArgs === 2) {
        return classnames2b(a, b);
    } else if (numArgs === 3) {
        return classnames3b(a, b, c);
    } else {
        return classnamesFlex2.apply(null, arguments);
    }
}

Tests:

classnames
classnames(null, "a");
classnames flex
classnamesFlex(null, "a");
classnames flex 2
classnamesFlex2(null, "a");
classnames 2
classnames2(null, "a");

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
classnames
classnames flex
classnames flex 2
classnames 2

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

Let's dive into the benchmark and explain what is being tested, compared, and their pros and cons.

**Benchmark Definition JSON**

The provided JSON represents a JavaScript microbenchmark for comparing different implementations of the `classnames` function. The `classnames` function is used to concatenate class names in a string. There are four variations:

1. `classnames(a, b)`: takes two arguments
2. `classnamesFlex(null, "a")`: uses the `filter` method and joins the resulting array with spaces
3. `classnamesFlex2()`: uses the `filter` method and joins the resulting array with spaces (similar to `classnamesFlex`, but without explicit null checks)
4. `classnames2(a, b)`: takes two arguments, similar to `classnames(a, b)`
5. The original implementation of `classnames(a, b)` is also provided for comparison

**Options Compared**

The options being compared are:

* `classnames(a, b)`: the original implementation
* `classnamesFlex(null, "a")`: uses `filter` method and joins with spaces
* `classnamesFlex2()`: uses `filter` method and joins with spaces (similar to `classnamesFlex`, but without explicit null checks)
* `classnames2(a, b)`: takes two arguments

**Pros and Cons of Each Approach**

1. **addClassnames(a, b)**:
	* Pros: concise, easy to read
	* Cons: may not handle all edge cases (e.g., no arguments)
2. **classnamesFlex(null, "a")**:
	* Pros: efficient, handles most edge cases
	* Cons: uses `filter` method, which can be slower than direct concatenation
3. **classnamesFlex2()**:
	* Pros: similar to `classnamesFlex`, but without explicit null checks
	* Cons: may not handle all edge cases (e.g., no arguments)
4. **addClassnames2(a, b)**:
	* Pros: similar to `addClassnames(a, b)`, but takes two arguments
	* Cons: may not handle all edge cases (e.g., one argument)

**Library and Purpose**

The `classnames` function uses the `filter` method and `join()` method from the JavaScript API. The `Filter` method is used to create a new array with elements that pass a test provided as a function.

**Special JS Feature or Syntax**

None of the implementations use any special features or syntax. They only rely on standard JavaScript APIs.

**Other Alternatives**

If you don't have access to the `classnames` function, you can implement it using different methods:

* **Using `concat()`**: `a + ' ' + b`
* **Using `array.join()`**: `[a, b].join(' ')`

Keep in mind that these alternatives may not be as efficient or concise as the original implementation.

I hope this explanation helps!

Latest run results:

Run details: (Test run date: 5 years ago)

User agent: Mozilla/5.0 (Mobile; LYF/LF-2403N/LYF-LF2403N-001-02-08-300518-i;Android; rv:48.0) Gecko/48.0 Firefox/48.0 KAIOS/2.5

Browser/OS: Firefox Mobile 48 on Firefox OS

View result in a separate tab

Test name	Executions per second
classnames	694560.2 Ops/sec
classnames flex	224797.8 Ops/sec
classnames flex 2	76483.8 Ops/sec
classnames 2	1323179.8 Ops/sec

Related benchmarks:

manual vs filter 2 (version: 0)

Comparing performance of: classnames vs classnames flex vs classnames flex 2 vs classnames 2

Created: 5 years ago by: Guest

Jump to the latest result

classnames

classnames flex

classnames flex 2

classnames 2

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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