Benchmark: Which equals operator (== vs ===) is faster?

Tests:

test equality
var n = 0; while(true) { n++; if(n==100000) break; }
test strict equality
var n = 0; while(true) { n++; if(n===100000) break; }
string to int
var n = 0; while(true) { n++; if(n=='100000') break; }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
test equality
test strict equality
string to int

Fastest: N/A

Slowest: N/A

Autogenerated LLM Sumamry (model gemma2:9b, generated 4 days ago):

LLMs can make mistakes. Check important info.

This benchmark investigates the performance difference between using the loose equality operator (`==`) and the strict equality operator (`===`) in JavaScript.

**Here's a breakdown:**

* **Test Cases:**

* **`test equality`**:  Compares an integer with another integer using `==`. 
    * **`test strict equality`**: Does the same comparison but uses `===`, which checks both value and data type.
    * **`string to int`**: Compares an integer to a string representation of the same number (`'100000'`), highlighting the potential for unexpected behavior with loose comparison.

* **Options Compared:**

* The primary options are `==` (loose equality) and `===` (strict equality). Loose equality performs type coercion, meaning it might convert values to a common type before comparison. Strict equality demands both value and type match.

* **Pros and Cons:**

* **`==`**:  
        * **Pro**: Can be more convenient when you're not strictly concerned about data types, as it handles type conversions automatically.
        * **Con**: Can lead to unexpected results due to type coercion. This can make your code harder to debug and understand.
    * **`===`**: 
        * **Pro**: Enforces strict equality checks, making your code more predictable and less prone to subtle bugs caused by type coercion.
        * **Con**:  Might require explicit type conversions if you need to compare values of different types.

**Key Considerations:**

* **Readability and Maintainability:** `===` generally improves code readability because its behavior is clearer and less prone to surprises.

* **Potential Performance Impact:** While the performance difference between `==` and `===` is usually negligible, it's worth considering in scenarios where performance is critical.  In most cases, the benefits of using `===` outweigh any minor performance differences.
**Alternatives:**

The benchmark doesn't explore alternatives, but depending on the specific use case, you might consider:

* **Type Guards**: If you're dealing with complex type systems (e.g., TypeScript), type guards can help ensure that values are used in a compatible manner.

Let me know if you have any other questions!

Latest run results:

Run details: (Test run date: 6 years ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/65.0.3325.181 Safari/537.36

Browser/OS: Chrome 65 on Linux

View result in a separate tab

Test name	Executions per second
test equality	6300.4 Ops/sec
test strict equality	6294.4 Ops/sec
string to int	881.4 Ops/sec

Related benchmarks:

Which equals operator (== vs ===) is faster? (version: 0)

Is there a performance benefit to replacing == with ===?

Comparing performance of: test equality vs test strict equality vs string to int

Created: 6 years ago by: Guest

Jump to the latest result

test equality

test strict equality

string to int

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Sumamry (model gemma2:9b, generated 4 days ago):