Benchmark: eval vs json parse use case

Tests:

eval
eval('var crop = {"condition":"AND","rules":[{"id":"Meta.CustomerDetails.EventTypeId","field":"Meta.CustomerDetails.EventTypeId","type":"integer","input":"select","operator":"equal","value":"3"}],"valid":true}');
parse
var crop = JSON.parse('{"condition":"AND","rules":[{"id":"Meta.CustomerDetails.EventTypeId","field":"Meta.CustomerDetails.EventTypeId","type":"integer","input":"select","operator":"equal","value":"3"}],"valid":true}');

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
eval
parse

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 28 days ago):

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks!

**Benchmark Overview**

The provided benchmark measures the performance difference between using `eval` and `JSON.parse` in a specific use case.

**Benchmark Definition**

The JSON definition for this benchmark consists of two individual test cases:

1. **`eval`**: This test case uses the `eval` function to parse a JSON string into an object.
2. **`parse`**: This test case uses the `JSON.parse` method to parse a JSON string into an object.

**What are we testing?**

In this benchmark, we're comparing the performance of two different approaches for parsing JSON strings:

*   **`eval`**: The `eval` function is a built-in JavaScript function that executes code provided as a string. In this case, it's used to parse a JSON string into an object.
*   **`JSON.parse`**: This method is specifically designed for parsing JSON strings into objects.

**Pros and Cons of Each Approach**

Here are some pros and cons of each approach:

### `eval`

**Pros:**

*   Simple and straightforward implementation
*   Can be used in various situations where dynamic code execution is required

**Cons:**

*   **Security risks**: Since `eval` executes arbitrary code, it can pose security threats if the input string is not properly sanitized.
*   **Performance overhead**: `eval` has a higher performance overhead compared to `JSON.parse`, especially for large JSON strings.

### `JSON.parse`

**Pros:**

*   **Faster execution**: `JSON.parse` is generally faster than `eval` since it's optimized for parsing JSON strings.
*   **Security-safe**: `JSON.parse` is designed specifically for parsing JSON strings and does not execute arbitrary code, reducing security risks.

**Cons:**

*   **More complex implementation**: While still relatively simple, `JSON.parse` requires more understanding of the JSON syntax and data types compared to `eval`.
*   **Limited flexibility**: Since `JSON.parse` is optimized for parsing JSON strings, it may not be suitable for other use cases that require dynamic code execution.

**Library: JSON**

In this benchmark, the `JSON` library is used implicitly. The `JSON.parse` method relies on the built-in `JSON` object in JavaScript to parse JSON strings into objects.

**Special JS Features/Syntax: None**

This benchmark does not utilize any special JavaScript features or syntax that would affect its performance comparison.

**Alternative Approaches**

If you need more control over the parsing process or require dynamic code execution, consider these alternative approaches:

*   **`JSON.stringify()` and `JSON.parse()`**: While not as fast as `eval`, this approach can be useful when working with complex data structures.
*   **Third-party JSON libraries**: Libraries like `jsonschema` or `fast-json-patch` provide more advanced features for parsing and validating JSON data.

Keep in mind that the choice of approach depends on your specific use case, performance requirements, and security constraints.

Latest run results:

Run details: (Test run date: 5 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.102 Safari/537.36

Browser/OS: Chrome 70 on Windows

View result in a separate tab

Test name	Executions per second
eval	154763.1 Ops/sec
parse	196204.1 Ops/sec

Related benchmarks:

eval vs json parse use case (version: 0)

Comparing performance of: eval vs parse

Created: 5 years ago by: Guest

Jump to the latest result

eval

parse

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 28 days ago):