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filter and then for vs for
(version: 0)
test
Comparing performance of:
Filter and then FOR vs just FOR
Created:
4 years ago
by:
Guest
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Tests:
Filter and then FOR
let arrayOne = ['A','B','C','B','C','D','E','v','C','D','C','D','E','v','v']; let result = []; arrayOne.filter(x => x === 'C').forEach(x => { result.push(x) })
just FOR
let arrayOne = ['A','B','C','B','C','D','E','v','C','D','C','D','E','v','v']; let result = []; arrayOne.forEach(x => { if(x === 'C'){ result.push(x); } })
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Filter and then FOR
just FOR
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Autogenerated LLM Summary
(model
gemma2:9b
, generated one year ago):
This benchmark compares two approaches to finding all occurrences of the letter 'C' within an array: **Approach 1: `filter` and then `forEach`:** * **Benchmark Definition:** ```javascript arrayOne.filter(x => x === 'C').forEach(x => { result.push(x) }) ``` * **Explanation:** This approach first uses the `filter()` method to create a new array containing only the elements from `arrayOne` that equal 'C'. Then, it iterates over this filtered array using `forEach()` and pushes each element into the `result` array. **Approach 2: `forEach` with a conditional:** * **Benchmark Definition:** ```javascript arrayOne.forEach(x => { if (x === 'C') { result.push(x); } }) ``` * **Explanation:** This approach directly iterates over the original array using `forEach()`. For each element, it checks if it's equal to 'C'. If so, it pushes the element into the `result` array. **Pros and Cons:** | Approach | Pros | Cons | |-------------------|----------------------------------------------|----------------------------------------------------| | `filter` & `forEach` | More readable, separates filtering from iteration | Potentially less efficient due to creating a new array | | `forEach` with conditional | Potentially more efficient as it avoids creating a new array | Less readable, logic is intertwined with iteration | **Other Considerations:** * **Array Size:** For very large arrays, the efficiency difference between these approaches might become more significant. * **Context:** In some cases, filtering first might be necessary even if it's slightly less efficient because it allows for further processing or manipulation of the filtered data before final iteration. **Alternatives:** * **`reduce()`:** This method could also be used to achieve the same result as `filter` and `forEach`. It iterates over the array, accumulating results in a single value. While more flexible, it might not be as immediately obvious for this specific use case.
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