Benchmark: [].call.slice() vs .slice()

Script Preparation code:

var arr = ['test', 1];

for (i = 0; i < 1000; i++) {
  arr.push(i);
}

Tests:

[].slice.call()
for (i = 0; i < 1000; i++) { [].slice.call(arr, 1) }
.slice()
for (i = 0; i < 1000; i++) { arr.slice(1) }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
[].slice.call()
.slice()

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/122.0.0.0 Safari/537.36

Browser/OS: Chrome 122 on Windows

View result in a separate tab

Test name	Executions per second
[].slice.call()	1322.3 Ops/sec
.slice()	1381.3 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks!

**Benchmark Overview**

The provided JSON represents a benchmark test case named `[].call.slice() vs .slice()` on MeasureThat.net. This test compares two approaches: using `[]` with the `call` method and using the dot notation (`.`) to access the `slice` method.

**Options Compared**

Two options are compared:

1. **Using `[]` with the `call` method**: This approach uses the `[]` array literal syntax and passes the object as an argument to the `call` method, which calls the `slice` method on that object.
2. **Using dot notation (`.`)**: This approach accesses the `slice` property directly using the dot notation.

**Pros and Cons**

**Using `[]` with the `call` method:**

Pros:

* Can be more readable in some cases, as it explicitly states the intent of calling a specific method on an object.
* May be more flexible if the object's structure changes in the future.

Cons:

* Adds unnecessary complexity to the syntax, which might make it harder for readers to understand the code.
* In modern JavaScript, this approach is not as common or widely supported as using dot notation.

**Using dot notation (`.`):**

Pros:

* More concise and idiomatic in most cases, as it's a standard way of accessing properties on objects.
* Easier to read and maintain, especially for developers familiar with object-oriented programming.

Cons:

* May be less readable if the property name is not obvious or well-known.

**Library and Special Features**

Neither option requires any external libraries. However, some JavaScript versions might optimize or handle these expressions differently. For example, in older browsers or versions of Node.js, `[]` with the `call` method might behave slightly differently due to differences in how objects are handled.

No special JavaScript features (like async/await, arrow functions, etc.) are used in this benchmark.

**Alternatives**

Other alternatives for accessing an object's properties include:

1. Bracket notation (`arr['property']`) or dot notation with a variable (`arr[variable]`).
2. Using the `in` operator to check if a property exists before accessing it (`if (prop in obj) { obj[prop]; }`).
3. Using a method like `hasOwnProperty()` on objects (not directly applicable here, as we're only using dot notation).

Keep in mind that these alternatives might have different performance characteristics or be more suitable for specific use cases.

**Benchmarking Results**

The latest benchmark results show that the `.slice()` approach is slightly faster than `[]` with the `call` method, with Chrome 122 running at approximately 1381.3 executions per second for `[].slice.call()`, compared to 1322.3 for `arr.slice(1)`. However, these differences are relatively small and might not be significant in most scenarios.

In summary, this benchmark test compares two common ways of accessing the `slice` method in JavaScript: using dot notation (`.`) and `[]` with the `call` method. While both approaches have their pros and cons, dot notation is generally considered more readable and idiomatic, while `[]` with the `call` method can add complexity to the syntax but might be more flexible.

Related benchmarks:

[].call.slice() vs .slice() (version: 0)

Comparing performance of: [].slice.call() vs .slice()

Created: 5 years ago by: Guest

Jump to the latest result

[].slice.call()

.slice()

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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