Benchmark: var1!==null vs var1!==undefined vs var1!=="x"

Script Preparation code:

var var1;

Tests:

var1!==null
if(var1!==null);
var1!==undefined
if(var1!==undefined);
var1!=="x"
if(var1!=="x");

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
var1!==null
var1!==undefined
var1!=="x"

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

Measuring the performance of JavaScript microbenchmarks is crucial to understand the efficiency of different approaches and identify potential bottlenecks in web applications.

**Benchmark Definition**

The provided JSON represents a benchmark that tests three different conditions:

1. `var1!==null` (Null Check)
2. `var1!==undefined` (Undefined Check)
3. `var1!==\"x\"` (String Comparison)

The script preparation code is simple: `var var1;`. This initializes the variable `var1` to an undefined state.

**Options Compared**

The benchmark compares three different approaches:

1. **Null Check**: `if(var1!==null)`
2. **Undefined Check**: `if(var1!==undefined)`
3. **String Comparison**: `if(var1!==\"x\")`

Each approach has its pros and cons:

* **Null Check**: This is a common way to check if a variable is null or undefined. However, it's not the most efficient way, as it involves a JavaScript interpreter call and can lead to unnecessary computations.
* **Undefined Check**: Similar to the Null Check, this checks if `var1` is undefined. It's also not the most efficient approach, but slightly better than the Null Check since it doesn't require an interpreter call.
* **String Comparison**: This is a simple comparison that only checks if the value of `var1` matches the string "x". It's likely to be faster than the other two approaches since it involves fewer computations and no interpreter calls.

**Library Usage**

In this benchmark, there is no explicit library usage. The script preparation code simply initializes the variable `var1`.

**Special JS Features/Syntax**

There are no special JavaScript features or syntax used in this benchmark.

**Other Considerations**

To get a more accurate understanding of the performance differences between these approaches, it's essential to consider other factors:

* **Context**: How is `var1` being used in the larger application? If it's being passed around as an argument to multiple functions, the performance differences may be less significant.
* **Browser/Platform**: Different browsers and platforms might optimize JavaScript differently, affecting the performance results.

**Alternatives**

For similar benchmarks, consider exploring other variations:

* Test different data types for `var1` (e.g., numbers, booleans, objects).
* Compare the performance of using `===`, `!==`, `==`, or `!=` operators.
* Use more complex variable assignments (e.g., function calls, object creation) to simulate real-world scenarios.

Keep in mind that JavaScript's behavior can be affected by various factors, such as engine optimizations, caching, and other browser-specific features. These alternatives can help you gain a deeper understanding of the nuances involved in JavaScript performance optimization.

Latest run results:

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

User agent: Mozilla/5.0 (iPad; CPU OS 14_8 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) CriOS/96.0.4664.53 Mobile/15E148 Safari/604.1

Browser/OS: Chrome Mobile iOS 96 on iOS 14.8

View result in a separate tab

Test name	Executions per second
var1!==null	14991078.0 Ops/sec
var1!==undefined	5243597.0 Ops/sec
var1!=="x"	15088138.0 Ops/sec

Related benchmarks:

var1!==null vs var1!==undefined vs var1!=="x" (version: 1)

Comparing performance of: var1!==null vs var1!==undefined vs var1!=="x"

Created: 3 years ago by: Registered User

Jump to the latest result

var1!==null

var1!==undefined

var1!=="x"

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):