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spread vs concat vs unshift v2
(version: 0)
spread vs concat vs unshift
Comparing performance of:
arrayUnshift123 vs arrayConcat123 vs arraySpread123
Created:
3 years ago
by:
Guest
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Script Preparation code:
var array = [...new Array(10000).keys()]; var insert = [...new Array(100).keys()];
Tests:
arrayUnshift123
array.unshift(...insert);
arrayConcat123
array = insert.concat(array)
arraySpread123
array = [...insert, ...array]
Rendered benchmark preparation results:
Suite status:
<idle, ready to run>
Run tests (3)
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Test case name
Result
arrayUnshift123
arrayConcat123
arraySpread123
Fastest:
N/A
Slowest:
N/A
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Autogenerated LLM Summary
(model
llama3.2:3b
, generated one year ago):
Let's break down the provided benchmark and explain what's being tested. **Benchmark Definition** The benchmark is testing three different ways to insert an array of elements into another array: 1. `array.unshift(...insert);` (unshift) 2. `array = insert.concat(array)` (concat) 3. `array = [...insert, ...array]` (spread) These methods are used to add elements to the end of an array in JavaScript. **Options Compared** The benchmark is comparing three different approaches: 1. **Unshift**: The `unshift()` method adds one or more elements to the beginning of an array. 2. **Concat**: The `concat()` method returns a new array containing all elements from both arrays. 3. **Spread**: The spread operator (`...`) is used to add elements to the end of an array. **Pros and Cons** * **Unshift**: + Pros: Efficient when inserting elements at the beginning of the array, as it only requires a single operation. + Cons: Can be slow for large arrays due to the overhead of searching for the correct insertion point. * **Concat**: + Pros: Simple to implement and widely supported. + Cons: Creates a new array, which can lead to increased memory usage and slower performance compared to other methods. * **Spread**: + Pros: Efficient and concise way to add elements to an array, as it avoids the overhead of searching for the correct insertion point. + Cons: Requires modern JavaScript engines (e.g., Node.js 14+) that support the spread operator. **Library and Special JS Features** There is no library mentioned in this benchmark. However, note that the `concat()` method uses the `concat()` function, which is a built-in JavaScript function. No special JavaScript features are being tested in this benchmark. All methods (unshift, concat, spread) are standard JavaScript syntax. **Alternatives** Other alternatives for inserting elements into an array include: 1. **Array.prototype.push()**: Adds one or more elements to the end of an array. 2. **Array.prototype.splice()**: Inserts one or more elements at a specific position in an array. 3. **Array.prototype.set()**: Sets the value of a single element in an array (not applicable here, as we're adding elements). Keep in mind that these alternatives might have slightly different performance characteristics compared to unshift, concat, and spread. Overall, this benchmark provides a simple yet insightful way to compare the performance of three common methods for inserting elements into an array.
Related benchmarks:
Splice vs Spread to insert at beginning of array
Splice vs Spread vs Unshift to insert at beginning of array
unshift vs spread vs concat
Splice vs Spread vs Unshift vs Concat to insert at beginning of array (fixed from slice)
spread vs concat vs unshift on 100000
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