Benchmark: slice vs substr vs substring 122459

Script Preparation code:

var string = "Hello World!"

Tests:

slice
string.slice(0, string.length - 7)
substr
string.substr(0, string.length - 7)
substring
string.substring(0, string.length - 7)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
slice
substr
substring

Fastest: N/A

Slowest: N/A

Latest run results:

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

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

**Benchmark Definition**
The benchmark definition represents a JavaScript microbenchmark that tests three different methods for extracting a substring from a given string: `slice`, `substr`, and `substring`. The test case is a simple string literal "Hello World!".

**Options Compared**
The three options compared are:

1. **`string.slice(0, string.length - 7)`**: This method returns a new string by extracting 7 characters from the beginning of the original string.
2. **`string.substr(0, string.length - 7)`**: This method returns a substring starting from index 0 and spanning `string.length - 7` characters.
3. **`string.substring(0, string.length - 7)`**: This method is similar to `substr`, but it's part of the JavaScript language syntax.

**Pros and Cons**

* **`slice()`**: Pros:
	+ Returns a new string, avoiding potential side effects on the original string.
	+ Can be faster due to its ability to bypass some browser optimizations.
* Cons:
	+ Requires explicit bounds checking (`string.length - 7`) to avoid indexing errors.
	+ Might not be optimized by modern browsers for this specific use case.
* **`substr()`**: Pros:
	+ Part of the JavaScript language syntax, so it's widely supported and understood.
	+ Typically faster than `slice()`, as it's a built-in method.
* Cons:
	+ Can return null or undefined if the index is out of bounds, which might be surprising for developers.
	+ Might not be optimized by modern browsers for this specific use case.
* **`substring()`**: Pros:
	+ Similar to `substr()`, but with explicit start and end indices (0 and `string.length - 7`, respectively).
	+ Typically faster than `slice()` due to its ability to bypass some browser optimizations.
* Cons:
	+ Part of the JavaScript language syntax, so it's widely supported and understood.

**Library and Purpose**
There is no library being used in this benchmark. The three methods (`slice()`, `substr()`, and `substring()`) are part of the JavaScript language itself.

**Special JS Feature or Syntax**
The test case uses the `length` property on the `string` object, which returns the number of characters in the string. This is a built-in JavaScript feature that allows accessing the length of a string without having to use external libraries or functions.

**Other Alternatives**

If you wanted to compare these methods with other alternatives, some options could include:

* Using regular expressions (e.g., `string.match(/^Hello /)` for extracting substrings starting from "Hello").
* Using third-party libraries like `lodash` (which has `lodash.string.prototype.slice`, `lodash.string.prototype.substr`, and `lodash.string.prototype.substring` methods).
* Comparing the performance of these methods with other programming languages, such as C++ or Java.

Keep in mind that these alternatives would require modifying the benchmark definition and test cases to accommodate the new methods.

Related benchmarks:

slice vs substr vs substring 122459 (version: 0)

slice vs substr vs substring in JS

Comparing performance of: slice vs substr vs substring

Created: 2 years ago by: Guest

Jump to the latest result

slice

substr

substring

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):