Benchmark: slice vs substr vs substrings

Script Preparation code:

var example = 'there is no spoon'

Tests:

slice
var result = example.slice(4, 8)
substring
var result = example.substring(4, 8)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
slice
substring

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36

Browser/OS: Chrome 131 on Linux

View result in a separate tab

Test name	Executions per second
slice	197847872.0 Ops/sec
substring	192581536.0 Ops/sec

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

LLMs can make mistakes. Check important info.

**What is tested in the provided JSON?**

The provided JSON represents a benchmark test that compares the performance of three different string slicing methods in JavaScript: `slice()`, `substring()`, and a custom implementation of "substrings" (which is not explicitly implemented in the provided code, but assumed to be a typo or an alternative name for one of the existing methods).

The test creates a single string variable `example` with the value `'there is no spoon'` and then runs each of the three slicing methods on this string. The results are stored in two separate test cases: "slice" and "substring".

**Options compared**

The options being compared are:

1. `slice()`
2. `substring()`
3. A custom implementation of "substrings" (not explicitly implemented in the provided code)

**Pros and Cons of each approach**

Here's a brief analysis of each approach:

1. **`slice()`**: This is a built-in JavaScript method that creates a new string by extracting a portion of an existing string. The pros are:
	* Performance: `slice()` is generally faster than `substring()` because it avoids the overhead of parsing and comparing the indices.
	* Conciseness: `slice()` requires fewer characters to express the same logic as `substring()`.
	* Consistency: `slice()` has a consistent behavior across different browsers and engines.

However, the cons are:
	* Limited control: `slice()` only returns a new string; it doesn't modify the original string.
2. **`substring()`**: This is also a built-in JavaScript method that creates a new string by extracting a portion of an existing string. The pros are:
	* Flexibility: `substring()` allows for more flexibility in terms of specifying both start and end indices, whereas `slice()` only takes one index as an argument.
3. **Custom "substrings" implementation**: Not implemented in the provided code, but assumed to be a typo or alternative name for one of the existing methods.

**Other considerations**

* The test doesn't consider the case where the start index is negative; if it were included, the results might differ significantly.
* The test assumes that the input string will always have at least two characters; if this isn't guaranteed, the results might not be representative.
* The browser used in the benchmark (Chrome 114) may have specific optimizations or quirks that affect the performance of these methods.

**Library and purpose**

None explicitly mentioned, but JavaScript built-in methods like `slice()` and `substring()` are part of the ECMAScript standard.

**Special JS feature or syntax**

None mentioned, as no special features or syntax are used in this benchmark.

Related benchmarks:

slice vs substr vs substrings (version: 0)

Compares slice, substr and substring to each other when there is only a start index

Comparing performance of: slice vs substring

Created: 2 years ago by: Guest

Jump to the latest result

slice

substring

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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