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Test length assign 1000
(version: 0)
Comparing performance of:
no var vs use var
Created:
3 years ago
by:
Guest
Jump to the latest result
Script Preparation code:
var obj = Array.from({ length: 1000 }).map((value, i) => i).reduce((val, v) => { val[v] = v; return val; }, {})
Tests:
no var
const entries = Object.values(obj); for (let i = 0; i < entries.length; i++) { const v = entries[i]; }
use var
const entries = Object.values(obj); const len = entries.length; for (let i = 0; i < len; i++) { const v = entries[i]; }
Rendered benchmark preparation results:
Suite status:
<idle, ready to run>
Run tests (2)
Previous results
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Test case name
Result
no var
use var
Fastest:
N/A
Slowest:
N/A
Latest run results:
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Autogenerated LLM Summary
(model
llama3.2:3b
, generated one year ago):
I'll explain what's being tested in the provided benchmark, describe the options compared, and discuss their pros and cons. **What is being tested?** The benchmark measures the execution time of two different approaches to iterate over an object's values: 1. Without using `var` (also known as "const" or "let" only): This approach uses `Object.values()` to get an array of object values, and then iterates over the array using a `for...of` loop. 2. With using `var`: This approach also uses `Object.values()` to get an array of object values, but assigns the length of the array to a variable (`len`) and then iterates over the array using a traditional `for` loop. **Options compared** The two options being tested are: * Option 1: Without `var`, using `const` or `let` only. + Pros: - Less prone to scope-related issues, as the variable is block-scoped and not function-scoped. - Can be more efficient in terms of memory allocation, as the array values are not redeclared in each iteration. + Cons: - May require additional setup or understanding of how `Object.values()` works. * Option 2: With `var`. + Pros: - More familiar and well-established syntax for many developers. - Can be easier to understand and work with, especially for those more experienced with older JavaScript versions. + Cons: - May lead to scope-related issues if not used carefully. - Can result in slower performance due to redeclaration of variables. **Library** The benchmark uses the `Object.values()` method, which is a part of the ECMAScript standard since ES6. This method returns an array of values from an object, with each value returned as an individual element of the array. **Special JS feature** This benchmark does not use any special JavaScript features such as async/await, promises, or closures. **Other alternatives** If you're interested in exploring alternative approaches to this benchmark, here are a few options: * Using `for...in` instead of `Object.values()` and iterating over the object's own enumerable properties. * Using a library like Lodash or Underscore.js to iterate over objects and arrays. * Writing a custom implementation for iterating over an object's values. Keep in mind that these alternatives may have different performance characteristics, syntax requirements, or memory usage compared to the benchmark options being tested.
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Test length assign
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