Benchmark: Javascript destructuring vs assign

Tests:

destructuring
const o = { offer: { offeredPrice: 119.99, discountPercentage: 50.5, }, course: { name: 'Direito', level: 'Bacharelado (graduação)', shift: 'Manhã', kind: 'Presencial', }, campus: { city: 'São Paulo', state: 'SP', neighborhood: 'Vila do Chavez', street: 'Rua 2', lat: '99999999999', lng: '-9999999999', }, university: { acronym: 'UNIVERSO', name: 'Universidade Universal do Estado de São Paulo', }, }; const { offer: { offeredPrice, discountPercentage, }, course: { name: courseName, level: courseLevel, shift: courseShift, kind: courseKind, }, campus: { city: campusCity, state: campusState, neighborhood: campusNeighborhood, street: campusStreet, lat: campusLng, lng: campusLat, }, university: { acronym: universityAcronym, name: universityName, }, } = o; console.log({ offeredPrice, discountPercentage, courseName, courseLevel, courseShift, courseKind, campusCity, campusState, campusNeighborhood, campusStreet, campusLng, campusLat, universityAcronym, universityName, });
assign
const o = { offer: { offeredPrice: 119.99, discountPercentage: 50.5, }, course: { name: 'Direito', level: 'Bacharelado (graduação)', shift: 'Manhã', kind: 'Presencial', }, campus: { city: 'São Paulo', state: 'SP', neighborhood: 'Vila do Chavez', street: 'Rua 2', lat: '99999999999', lng: '-9999999999', }, university: { acronym: 'UNIVERSO', name: 'Universidade Universal do Estado de São Paulo', }, }; console.log({ offeredPrice: o.offer.offeredPrice, discountPercentage: o.offer.discountPercentage, courseName: o.course.name, courseLevel: o.course.level, courseShift: o.course.shift, courseKind: o.course.kind, campusCity: o.campus.city, campusState: o.campus.state, campusNeighborhood: o.campus.neighborhood, campusStreet: o.campus.street, campusLng: o.campus.lng, campusLat: o.campus.lat, universityAcronym: o.university.acronym, universityName: o.university.name, });

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Previous results

Test case name	Result
destructuring
assign

Fastest: N/A

Slowest: N/A

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Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):

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Let's break down the benchmark and explain what's being tested.

**Benchmark Definition**

The benchmark is defined as follows:

* Two test cases: "destructuring" and "assign".
* Each test case uses a JSON object `o` with nested properties (e.g., `offer`, `course`, `campus`, `university`).

**Test Cases**

There are two test cases:

1. **Destructuring**: This test case extracts values from the JSON object `o` using destructuring syntax, which is a feature introduced in JavaScript 2015 (ES6). The syntax is as follows:
```javascript
const { offer: { offeredPrice, discountPercentage }, course: { name, level, shift, kind }, campus: { city, state, neighborhood, street, lat, lng }, university: { acronym, name } } = o;
```
The test case measures the performance of this destructuring syntax.

2. **Assign**: This test case assigns values from the JSON object `o` to variables using dot notation or bracket notation, which is a more traditional way of accessing properties in JavaScript:
```javascript
console.log({
  offeredPrice: o.offer.offeredPrice,
  discountPercentage: o.offer.discountPercentage,
  courseName: o.course.name,
  // ...
});
```
The test case measures the performance of this assignment syntax.

**Library and Special JS Feature**

Both test cases use built-in JavaScript features, so there are no external libraries involved. However, it's worth noting that destructuring syntax is a relatively new feature introduced in ES6 ( ECMAScript 2015), which may not be supported by older browsers or engines.

**Options Compared**

The two test cases compare the performance of two different syntaxes for accessing and extracting values from a JSON object:

* Destructuring syntax (ES6+)
* Assignment syntax (traditional)

**Pros and Cons**

Here are some pros and cons of each approach:

* **Destructuring Syntax:**
	+ Pros:
		- More concise and expressive
		- Reduces the need for explicit variable declarations
		- Can improve code readability
	+ Cons:
		- May not be supported by older browsers or engines
		- Can be less intuitive for developers who are new to this syntax
* **Assignment Syntax:**
	+ Pros:
		- Widely supported across different browsers and engines
		- Easy to understand and implement for developers familiar with traditional JavaScript
	+ Cons:
		- Can lead to more verbose code
		- May require explicit variable declarations, which can add clutter

**Other Considerations**

When choosing between destructuring syntax and assignment syntax, consider the following factors:

* Code readability: If your code is meant to be readable by others (or yourself in the future), destructuring syntax might be a better choice.
* Browser support: If you need to support older browsers or engines, assignment syntax might be a safer bet.
* Performance: Both approaches have similar performance characteristics, so this factor may not be a deciding one.

**Alternatives**

If you're looking for alternative ways to access and extract values from a JSON object, consider the following options:

* **Object destructuring**: Similar to the test case, but with a more concise syntax:
```javascript
const { offer: { offeredPrice, discountPercentage }, course: { name, level, shift, kind } } = o;
```
* **Array destructuring**: Another variation of object destructuring, suitable for objects with array-like properties:
```javascript
const [offer, course] = [o.offer, o.course];
```
Keep in mind that these alternatives have similar pros and cons to the test case syntax.

I hope this explanation helps you understand what's being tested in the benchmark!

Related benchmarks:

Javascript destructuring vs assign (version: 0)

Comparing performance of: destructuring vs assign

Created: 3 years ago by: Registered User

Jump to the latest result

destructuring

assign

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):