Benchmark: slice vs substr vs substring (with no end index)

Script Preparation code:

var example = 'there is no spoon'

Tests:

slice
var result = example.slice(10)
substr
var result = example.substr(10)
substring
var result = example.substring(10)

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

Autogenerated LLM Sumamry (model llama3.2:3b, generated 16 days ago):

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and explain what's being tested, compared, and some of the pros and cons associated with each approach.

**Benchmark Overview**

The benchmark is designed to compare the performance of three JavaScript methods: `slice()`, `substr()`, and `substring()` when used without an end index. The test case uses a predefined string `example` created in the Script Preparation Code, which contains the phrase "there is no spoon".

**What's being compared**

The benchmark compares the execution speed of each method across different browsers (Opera 114) on various devices (Desktop).

**Options Compared**

1. **slice()**: This method returns a new string slice from the original string.
2. **substr()**: This method returns a portion of the string specified by the start index and length.
3. **substring()**: This method is similar to `substr()` but does not include the end index.

**Pros and Cons**

*   **slice()**:
    *   Pros: Generally faster than `substr()` or `substring()` because it doesn't require an explicit length parameter.
    *   Cons: Doesn't account for the potential performance difference between different browsers' implementations of string slicing.
*   **substr()** and **substring()**:
    *   Pros: Explicitly specify the start index, which can be useful in some cases (e.g., avoiding unnecessary memory allocation).
    *   Cons: Potentially slower than `slice()` due to the additional parameter required.

**Library or Special JS Feature**

None of the methods being compared rely on any specific library or feature. However, it's worth noting that modern JavaScript engines often provide optimized implementations for string manipulation methods like these.

**Considerations**

The benchmark assumes a fixed string length and doesn't account for variations in input sizes or complexities. This might lead to inaccurate results when testing with different inputs.

**Alternative Approaches**

Other approaches to compare the performance of `slice()`, `substr()`, and `substring()` could include:

*   Using larger input strings
*   Incorporating more browsers or devices into the benchmark
*   Accounting for differences in JavaScript engine optimizations across various platforms
*   Examining the impact of string normalization or encoding on method performance

These alternatives can provide a more comprehensive understanding of the methods' performance characteristics and help ensure accurate results.

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/129.0.0.0 Safari/537.36

Browser/OS: Chrome 129 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
slice	15710837.0 Ops/sec
substr	15879471.0 Ops/sec
substring	15759004.0 Ops/sec

Related benchmarks:

slice vs substr vs substring (with no end index) (version: 1)

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

Comparing performance of: slice vs substr vs substring

Created: 6 years ago by: Registered User

Jump to the latest result

slice

substr

substring

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Sumamry (model llama3.2:3b, generated 16 days ago):