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property assign vs spread operator
(version: 0)
Comparing performance of:
property assignment vs spread operator
Created:
6 years ago
by:
Guest
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Tests:
property assignment
var params = { b:"hello", c: true, d:7 }; for (var i = 0; i < 10000; i++) { params[i] = i; }
spread operator
var params = { b:"hello", c: true, d:7 }; for (var i = 0; i < 10000; i++) { params = { [i]: i, ...params}; }
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Suite status:
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Test case name
Result
property assignment
spread operator
Fastest:
N/A
Slowest:
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Autogenerated LLM Summary
(model
gemma2:9b
, generated one year ago):
This benchmark compares two ways of adding properties to an object in JavaScript: **Option 1: Property Assignment** - The code iterates 10,000 times and adds a new property `i` to the `params` object for each iteration. - It uses traditional dot notation or bracket notation (`params[i] = i;`) to assign values directly to new properties. **Option 2: Spread Operator** - This approach uses the spread operator (`...`) to merge a new object containing a single property `i` with the existing `params` object in each iteration. - The syntax looks like this: `params = { [i]: i, ...params};`. **Pros and Cons:** * **Property Assignment (Option 1):** * **Pros:** * Simple and straightforward to understand. * Potentially faster for creating many new properties sequentially. * **Cons:** * Can result in larger object sizes if you're adding a lot of properties, as each property requires its own space. * **Spread Operator (Option 2):** * **Pros:** * More concise syntax when updating existing properties and adding new ones. * Can be more efficient for large datasets by avoiding the creation of many individual properties. * **Cons:** * Might not be as performant as direct assignment for very small numbers of properties due to object merging overhead. **Other Considerations:** - The performance difference between these methods can be subtle and highly dependent on factors like: * The size of the object. * The number of iterations. * The JavaScript engine being used (different engines have different optimizations). **Alternatives:** - **Maps:** If you need to frequently add and remove key-value pairs, Maps might be a better choice than objects as they are designed for that purpose and often perform better for large datasets. Let me know if you'd like to explore any of these concepts in more detail!
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