Benchmark: slice vs substr vs substring (with no end index) - 2

Script Preparation code:

var example = 'The quick brown fox jumps over the lazy dog.';

Tests:

slice
var result = example.slice(0,19)
substr
var result = example.substr(0,19)
substring
var result = example.substring(0,19)

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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I'll break down the provided JSON data and explain what's being tested, compared, and some pros and cons of different approaches.

**Benchmark Definition**

The benchmark definition is a JSON object that contains metadata about the test. It includes:

* `Name`: A unique name for the benchmark.
* `Description`: A brief description of the test.
* `Script Preparation Code`: The JavaScript code used to prepare the test data. In this case, it's just an example string `var example = 'The quick brown fox jumps over the lazy dog.';`.
* `Html Preparation Code`: Not applicable in this case.

**Individual Test Cases**

There are three test cases:

1. `slice`
2. `substr`
3. `substring`

These test cases compare the performance of three different methods to extract a substring from the `example` string:

* `slice(start, end)`: Returns a new string containing all characters from the start index up to but not including the end index.
* `substr(start, length)`: Returns a new string containing all characters from the start index for the specified length.
* `substring(start, length)`: (Note: This method is deprecated in ECMAScript 5 and later versions. It's still available for backward compatibility.)

**Performance Comparison**

The performance comparison is between these three methods:

* **slice**: Creates a new string by copying the characters from the start index to the end index.
* **substr**: Creates a new string by copying the specified length of characters from the start index.
* **substring**: (Deprecated) Creates a new string by copying the specified length of characters from the start index.

**Pros and Cons**

Here's a brief summary:

* `slice`:
	+ Pros: Generally faster than `substr` and `substring`, as it doesn't require creating an intermediate array or copy.
	+ Cons: Creates a new string, which can lead to memory allocation overhead if the input is large.
* `substr`:
	+ Pros: Similar performance to `slice`, but may be slightly slower due to the additional length parameter.
	+ Cons: Requires creating an intermediate array or copy, which can impact performance for large inputs.
* **substring** (Deprecated):
	+ Pros: None.
	+ Cons: Deprecate since ECMAScript 5, and its behavior is not guaranteed in newer browsers.

**Library Usage**

None of the test cases use any external libraries. The JavaScript code is self-contained within each test case.

**Special JS Features/Syntax**

There are no special features or syntax used in these test cases beyond standard ECMAScript syntax.

**Alternatives**

For benchmarking similar operations, you could consider testing other methods like:

* `indexOf()` and `slice()` to extract a substring
* Regular expressions (`RegExp`) for substring extraction
* String concatenation (`+` operator) or template literals for substring creation

Keep in mind that these alternatives may introduce additional complexity or overhead not present in the original benchmark.

Related benchmarks:

slice vs substr vs substring (with no end index) - 2 (version: 0)

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

Comparing performance of: slice vs substr vs substring

Created: 5 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):