Benchmark: isNumber: regex vs isNaN (version: 2)

HTML Preparation code:


<script src='https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.min.js'></script>

Script Preparation code:

window.case1 = new Proxy({}, {
  get(t, p, r) {
    if (!isNaN(p)) {
      return +p
    }
    else {
      return Reflect.get(t, p, r)
    }
  }
});
window.case2 = new Proxy({}, {
  get(t, p, r) {
    if (/^\d+$/.test(p)) {
      return +p
    }
    else {
      return Reflect.get(t, p, r)
    }
  }
});
window.gabage1 = 0;
window.gabage2 = 0;

Tests:

isNaN
gabage1 =+ case1[_.random(0, 1e3, false)];
regex
gabage2 =+ case2[_.random(0, 1e3, false)];

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
isNaN
regex

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

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

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**Benchmark Overview**

The provided benchmark compares two approaches to check if a value is a number: `isNaN` (version 2) and a regular expression (`/^\d+$/`). The goal is to determine which approach is faster.

**Script Preparation Code**

The script preparation code defines two Proxy objects, `case1` and `case2`, which are used to wrap the benchmarking function. These Proxies allow us to intercept property access on the wrapped object. The code also initializes two garbage variables, `gabage1` and `gabage2`, to 0.

The HTML preparation code includes a script tag that loads Lodash.js, a utility library that provides the `_` function used in the benchmarking code.

**Benchmark Test Cases**

There are two test cases:

1. **`isNaN`**: This test case checks if the value of `gabage1` (or `gabage2`) is not a number using the `isNaN` function.
2. **`regex`**: This test case checks if the value of `gabage1` (or `gabage2`) is a number using a regular expression (`/^\d+$/`).

**Options Compared**

The two approaches are compared:

* **`isNaN`**: Uses the built-in `isNaN` function to check if a value is not a number.
* **`regex`**: Uses a regular expression to match only numeric strings.

**Pros and Cons of Each Approach**

1. **`isNaN`**:
	* Pros: Simple, widely supported, and fast.
	* Cons: May return false positives for certain types of numbers (e.g., NaN) or non-numeric values (e.g., `NaN`, `undefined`, or `null`).
2. **`regex`**:
	* Pros: More precise than `isNaN`, as it only matches numeric strings.
	* Cons: Slower and less widely supported, especially in older browsers.

**Lodash Library**

The Lodash library is used to generate random numbers for the benchmarking code using the `_` function. In this case, the `_random` function generates a random number between 0 and 1 millisecond (inclusive).

**Special JS Feature/Syntax**

There are no specific JavaScript features or syntaxes mentioned in the benchmark definition.

**Other Alternatives**

If you want to implement your own regular expression to check if a value is a number, you can use a similar approach using `/^\d+$/`. However, keep in mind that this will not be as fast or efficient as using the built-in `isNaN` function.

It's also worth noting that there are other approaches to check if a value is a number, such as using `Number.isFinite` or `Number.isInteger`, which may offer better performance and accuracy than the `isNaN` approach.

Related benchmarks:

isNumber: regex vs isNaN (version: 2) (version: 0)

Comparing performance of: isNaN vs regex

Created: 5 years ago by: Guest

Jump to the latest result

isNaN

regex

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):