Benchmark: typeof vs boolean for obj

Script Preparation code:

var obj = {hello: "world"};

Tests:

boolean
Boolean(obj)
typeof
typeof obj === 'object'
dnegation
!!obj

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
boolean
typeof
dnegation

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/121.0.0.0 Safari/537.36 OPR/107.0.0.0

Browser/OS: Opera 107 on Windows

View result in a separate tab

Test name	Executions per second
boolean	7229214.0 Ops/sec
typeof	19604720.0 Ops/sec
dnegation	18280112.0 Ops/sec

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

LLMs can make mistakes. Check important info.

**Benchmark Explanation**

The provided benchmark, hosted on MeasureThat.net, compares the performance of three different approaches to determine whether an object is boolean or not in JavaScript.

**Approaches Compared:**

1. **Boolean function**: `Boolean(obj)`. This approach uses the built-in `Boolean` function to convert the `obj` value into a boolean.
2. **Type checking using `typeof`**: `typeof obj === 'object'`. This approach checks if the type of `obj` is an object using the `typeof` operator.
3. **Negation with double bang `!!`**: `!!obj`. This approach uses the double bang (`!!`) operator to negate the boolean value of `obj`.

**Pros and Cons:**

*   **Boolean function (`Boolean(obj)`)**:
    *   Pros: Simple, straightforward, and widely supported.
    *   Cons: May be slower due to additional overhead (function call).
*   **Type checking using `typeof` (`typeof obj === 'object'`)**:
    *   Pros: Fast, as it directly checks the type without any overhead. Also, this is how JavaScript would typically check for an object's type.
    *   Cons: Requires knowledge of the `typeof` operator and its nuances (e.g., handling null or undefined values).
*   **Negation with double bang `!!` (`!!obj`)**:
    *   Pros: Simple, as it leverages a common JavaScript idiom for checking boolean values.
    *   Cons: May be slower due to the negation operation and potential browser inconsistencies.

**Library Usage**

None of the approaches explicitly use any libraries.

**Special JS Feature/Syntax**

The benchmark uses double bang (`!!`) operator, which is a special syntax in JavaScript. The `!!` operator is called "double not" or "bang notation," and it's used to negate a boolean value (i.e., convert true to false and vice versa). This syntax can be less intuitive for some developers.

**Other Alternatives**

In addition to the above approaches, other alternatives could include:

*   Using `obj === null` or `obj === undefined` to check if an object is falsy.
*   Utilizing a library like `lodash` or `es6-promise`, which provide more advanced boolean checking utilities.

However, these alternative approaches are not included in the provided benchmark and may be considered less standard or less efficient compared to the directly used methods (`Boolean(obj)`, `typeof obj === 'object'`, and `!!obj`).

Related benchmarks:

typeof vs boolean for obj (version: 0)

Comparing performance of: boolean vs typeof vs dnegation

Created: 2 years ago by: Guest

Jump to the latest result

boolean

typeof

dnegation

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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