Benchmark: eval vs json parse2

Tests:

eval
eval('[1,2,3,4];');
parse
var crop = JSON.parse('[1,2,3,4]');

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
eval
parse

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 17_3_1 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/17.3.1 Mobile/15E148 Safari/604.1

Browser/OS: Mobile Safari 17 on iOS 17.3.1

View result in a separate tab

Test name	Executions per second
eval	9428819.0 Ops/sec
parse	7463903.5 Ops/sec

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

LLMs can make mistakes. Check important info.

I'll break down the provided benchmark and its options, highlighting their pros and cons.

**Benchmark Overview**

The benchmark compares the execution time of two JavaScript functions: `eval()` and `JSON.parse()`. The test cases measure how quickly these functions can parse an array `[1,2,3,4]`.

**Test Cases**

There are two test cases:

1. **`eval()`**: This function takes a string as input and evaluates it as JavaScript code.
2. **`JSON.parse()`**: This function parses a JSON-formatted string into a JavaScript object.

**Options Compared**

The two options being compared are:

* `eval()`: Evaluates the array `[1,2,3,4]` as JavaScript code.
	+ Pros:
		- Can parse arrays and objects in a more flexible way.
		- Allows for dynamic code execution.
	+ Cons:
		- Can be slower due to security restrictions (e.g., evaluating user-provided input).
		- Can introduce security vulnerabilities if not used carefully.
* `JSON.parse()`: Parses the array `[1,2,3,4]` as a JSON-formatted string.
	+ Pros:
		- Faster execution time compared to `eval()`.
		- More secure, as it only parses valid JSON input.
	+ Cons:
		- Limited flexibility in parsing complex data structures.

**Library Used**

Neither test case explicitly uses a library. However, both functions rely on the JavaScript standard library:

* `eval()` uses the `Function` constructor or the `new Function()` syntax to execute the code.
* `JSON.parse()` uses the built-in `JSON` object and its `parse()` method.

**Special JS Feature**

Neither test case explicitly utilizes a special JavaScript feature. However, the benchmark may be affected by:

* **Array literal syntax**: The array `[1,2,3,4]` is used as input to both functions.
* **Type coercion**: The array is coerced into a numeric type in some browsers.

**Alternatives**

If you were to rewrite these test cases using alternative approaches, consider the following options:

* Use `JSON.stringify()` and `slice()` instead of `eval()`: This would parse the array as a JSON-formatted string, similar to `JSON.parse()`.
* Use `Array.from()` or other methods to create an array from user input: This could help evaluate the performance impact of using `eval()` versus `JSON.parse()`.
* Compare parsing times for different data formats (e.g., objects, dates, numbers): This would provide a more comprehensive understanding of each function's performance.

Keep in mind that these alternatives might not directly compare to the original test cases, but they could offer new insights into JavaScript's performance and security.

Related benchmarks:

eval vs json parse2 (version: 0)

Comparing performance of: eval vs parse

Created: 2 years ago by: Guest

Jump to the latest result

eval

parse

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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