Benchmark: eval vs json parse - om

Tests:

eval
var crop = 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: one year ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/135.0.0.0 Safari/537.36

Browser/OS: Chrome 135 on Windows

View result in a separate tab

Test name	Executions per second
eval	10454581.0 Ops/sec
parse	14898381.0 Ops/sec

Autogenerated LLM Summary (model gpt-4o-mini, generated one year ago):

LLMs can make mistakes. Check important info.

This benchmark compares the performance of two JavaScript methods: `eval` and `JSON.parse`, specifically in the context of parsing a string representation of an array, which in this case is `'[1,2,3,4]'`.

### Options Compared

1. **`eval` Method:**
   - **Benchmark Definition:** `var crop = eval('[1,2,3,4]');`
   - **Test Name:** `eval`
   
   The `eval` function takes a string as input and executes it as JavaScript code. In this case, it interprets the string `'[1,2,3,4]'` and converts it into an actual JavaScript array.

**Pros:**
   - Flexibility: Can execute any JavaScript code, not just data parsing.
   - Can evaluate expressions that may not be purely data.

**Cons:**
   - Security: Using `eval` can introduce significant security vulnerabilities, particularly if the input data is not trusted, as it can execute arbitrary code.
   - Performance: Generally slower due to the complexity of parsing and executing arbitrary code.

2. **`JSON.parse` Method:**
   - **Benchmark Definition:** `var crop = JSON.parse('[1,2,3,4]');`
   - **Test Name:** `parse`

The `JSON.parse` method specifically parses a JSON string and constructs the JavaScript value or object described by that string. Here, it reads the string representation `'[1,2,3,4]'` and directly converts it into an array.

**Pros:**
   - Security: Safer than `eval`, as it only processes well-formed JSON strings and is not capable of executing arbitrary code.
   - Performance: Typically faster than `eval` for parsing, as it is optimized for this specific task.

**Cons:**
   - Less flexible: Can only parse valid JSON and cannot execute code or expressions.

### Performance Results

From the benchmark results:
- `JSON.parse` achieved **14,898,381** executions per second.
- `eval` achieved **10,454,581** executions per second.

This indicates that `JSON.parse` outperforms `eval` in this scenario, which aligns with the expected behavior since `JSON.parse` is designed for direct JSON data parsing and has optimizations in place for structured data, whereas `eval` has overhead associated with handling general JavaScript code execution.

### Other Considerations

- **Alternatives to `eval` and `JSON.parse`:** 
  - For converting other data formats (like XML or custom structures), developers might use libraries tailored for those formats (e.g., XML parsers).
  - For more complex data manipulations, libraries such as Lodash can be employed, although they typically serve broader data manipulation purposes beyond parsing.

Overall, in scenarios where you need to parse a JSON string, `JSON.parse` is the recommended approach due to its performance efficiency and security considerations. Using `eval` should be discouraged unless absolutely necessary, and even then, alternative strategies should be considered to avoid security risks.

Related benchmarks:

eval vs json parse - om (version: 1)

Comparing performance of: eval vs parse

Created: one year 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 gpt-4o-mini, generated one year ago):