Benchmark: eval vs new Function (including parse)

Tests:

eval
eval('(function test() { return 2 * 3 })()')
new Function
(new Function("return 2 * 3"))()

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
eval
new Function

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/105.0.0.0 Safari/537.36 Edg/105.0.1343.50

Browser/OS: Chrome 105 on Windows

View result in a separate tab

Test name	Executions per second
eval	3395938.2 Ops/sec
new Function	1675908.6 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the benchmark and explain what is being tested.

**Benchmark Overview**

The benchmark is designed to compare two different approaches: `eval` and `new Function`. The goal is to measure which approach is faster for executing small JavaScript functions.

**Options Compared**

The two options being compared are:

1. **`eval`**: A built-in JavaScript function that parses and executes a string as JavaScript code.
2. **`new Function` (or `Function()` constructor)**: A way to create a new, anonymous function dynamically using the `Function` constructor.

**Pros and Cons**

* **`eval`**:
	+ Pros:
		- Simple to use
		- Works well for small, simple expressions
	+ Cons:
		- Can be vulnerable to security risks (e.g., code injection) if not used carefully
		- May be slower than `new Function` due to the overhead of parsing and executing the string as JavaScript code
* **`new Function`**:
	+ Pros:
		- More secure than `eval`, as it prevents code injection attacks
		- Can be faster than `eval`, especially for larger expressions, since it avoids the overhead of parsing and executing the string as JavaScript code
	+ Cons:
		- Requires a bit more boilerplate code to define the function (e.g., using template literals or string formatting)
		- May be slower than `eval` for very small expressions due to the creation overhead of the new function object

**Library/Feature Considerations**

There is no library used in this benchmark. However, it's worth noting that other approaches, like `Function()` with a single argument (e.g., `new Function('return 2 * 3;')`), can also be used to create dynamic functions.

**Special JS Feature/Syntax**

There are no special JavaScript features or syntax being tested in this benchmark. The focus is on the performance comparison between `eval` and `new Function`.

**Other Alternatives**

If you need to compare other approaches, here are a few alternatives:

* **`Function()` with multiple arguments**: Similar to `new Function`, but allows passing arguments when creating the function.
* **`Array.prototype.push.call` or similar methods**: Can be used to create dynamic functions in a more concise way (e.g., using `push.apply(function(arr) { arr[0] = 2; }([])`).
* **ES6 template literals**: Can be used to create simple, one-liner expressions as strings (e.g., `eval('(() => 2 * 3)(())')`).

Keep in mind that these alternatives might not provide the same performance benefits as `new Function`, and some may have different trade-offs in terms of security or conciseness.

Related benchmarks:

eval vs new Function (including parse) (version: 0)

Comparing performance of: eval vs new Function

Created: 2 years ago by: Guest

Jump to the latest result

eval

new Function

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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