Benchmark: for continue vs filter

Script Preparation code:

var array = Array(5000).fill(0).concat(Array(5000).fill(1));
var filteredArray = [];

Tests:

for continue
for (item of array) { if(item['id'] > 0.5) continue; filteredArray.push(item) }
filter
for (item of array.filter(el => el['id'] > 0.5)){ filteredArray.push(item) }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
for continue
filter

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 7 months ago)

User agent: Mozilla/5.0 (X11; Linux aarch64) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/60.5 Safari/605.1.15

Browser/OS: Safari 60 on Linux

View result in a separate tab

Test name	Executions per second
for continue	103.5 Ops/sec
filter	317.8 Ops/sec

Autogenerated LLM Summary (model gpt-4o-mini, generated 7 months ago):

LLMs can make mistakes. Check important info.

The benchmark provided compares two different approaches for filtering elements from an array in JavaScript: a traditional `for` loop with a `continue` statement and the `Array.prototype.filter()` method.

### Benchmark Options

1. **For Loop with Continue**
   - **Code**: 
     ```javascript
     for (item of array) {
       if(item['id'] > 0.5) continue;
       filteredArray.push(item);
     }
     ```
   - **Pros**: 
     - This method allows for full control over the iteration. Engineers can easily insert additional logic, manipulate indices, or break out of the loop based on complex conditions.
     - It can potentially be more efficient in some cases as it avoids the overhead of creating a new array that the `filter` method would require.
   - **Cons**: 
     - It can result in less readable and more error-prone code, particularly when the logic grows complex.
     - There's a risk of a higher cognitive load when maintaining the loop’s logic.

2. **Array.prototype.filter**
   - **Code**: 
     ```javascript
     for (item of array.filter(el => el['id'] > 0.5)) {
       filteredArray.push(item);
     }
     ```
   - **Pros**:
     - Highly readable and expressive, making it clear that this operation is filtering an array based on a condition.
     - It allows for cleaner function composition and can help with chaining methods in functional programming paradigms.
   - **Cons**:
     - The `filter` method creates a new array, which can introduce an overhead in terms of performance and memory consumption, especially for large datasets, as you are maintaining two arrays in memory.
     - It may be less efficient in cases where the running environment or the specific context of the dataset makes the overhead unnecessary.

### Additional Considerations
- **Performance**: According to the latest benchmark results from Safari 60, the `filter` method executed at approximately 317.79 operations per second, while the `for continue` loop executed at around 103.48 operations per second. This indicates that the `filter` method is significantly faster under the given testing conditions, which may be surprising given the traditional assumption that manual loops are always more performant.
  
- **Readability vs. Performance**: The choice between these two methods often boils down to a trade-off between readability and raw performance. In many situations, using `filter` enhances code clarity at the cost of potential performance degradation with larger datasets. However, with the results showing `filter` as the faster option in this benchmark, it may be prudent to prefer `filter` unless profiling shows otherwise.

### Alternatives
- **Using `forEach`**: Another commonly used approach would be to use `Array.prototype.forEach()` to iterate over the array and conditionally push elements. However, `forEach` does not allow for early exits with `break` or `continue`.
- **Traditional `for` Loop**: A classic `for` loop (for example, `for (let i = 0; i < array.length; i++)`) could be used, which provides maximum flexibility to control the iteration but may lead to similar readability concerns as the first approach.
- **Libraries such as Lodash**: Employing utility libraries like Lodash can provide methods like `_.filter` which is a syntactically cleaner way to filter arrays while still being performant.

Overall, choosing the right approach should consider specific use cases, team standards, and the environment in which the code will run.

Related benchmarks:

for continue vs filter (version: 1)

Comparing performance of: for continue vs filter

Created: 7 months ago by: Guest

Jump to the latest result

for continue

filter

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model gpt-4o-mini, generated 7 months ago):