Benchmark: index vs lastindexof empty

Tests:

lastIndexOf
var str = "According to that, indexOf is just a little bit faster. Of course, it does depend on what you are indexing.IndexOf looks for the first occurrence and lastIndexOf returns to the last occurrence. That all said, their are much better functions around now like map.To be honest though, if Google is using it there is probably a good reason."; var n = str.lastIndexOf("havent string");
indexOf
var str = "According to that, indexOf is just a little bit faster. Of course, it does depend on what you are indexing.IndexOf looks for the first occurrence and lastIndexOf returns to the last occurrence. That all said, their are much better functions around now like map.To be honest though, if Google is using it there is probably a good reason."; var n = str.indexOf("havent string");

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
lastIndexOf
indexOf

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

This benchmark does not have any results yet. Be the first one to run it!

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 on MeasureThat.net.

**Benchmark Overview**

The provided benchmark compares two related but distinct functions in JavaScript: `indexOf` and `lastIndexOf`. These functions are used to find the position of a specified value within a string.

**Functions Compared**

1. `indexOf(str, search)`: Returns the index of the first occurrence of `search` within `str`, or -1 if not found.
2. `lastIndexOf(str, search)`: Returns the index of the last occurrence of `search` within `str`, or -1 if not found.

**Options Compared**

The benchmark compares the performance of these two functions:

* Using `indexOf`
* Using `lastIndexOf`

**Pros and Cons of Each Approach**

1. **`indexOf`**:
	* Pros: Typically faster than `lastIndexOf` because it only searches for the first occurrence.
	* Cons: May return incorrect results if the search string is not found, but returns -1 to indicate this.
2. **`lastIndexOf`**:
	* Pros: Returns the index of the last occurrence, which can be useful in certain scenarios.
	* Cons: Typically slower than `indexOf` because it searches from the end of the string.

**Library and Special JS Features**

In neither test case is a library used. However, both benchmarks use JavaScript's built-in string methods (`indexOf`, `lastIndexOf`). There are no special features or syntax mentioned in the benchmark definitions.

**Other Alternatives**

If you need to perform substring searching in JavaScript, there are other options:

1. **Regular expressions**: Use `RegExp` objects with the `exec()` method to search for patterns in strings.
2. **String.prototype.indexOf() and String.prototype.lastIndexOf() equivalents**: Some browsers or environments might have different implementations of these methods.

For example, if you wanted to use regular expressions to find a substring, your code would look like this:
```javascript
var str = "Hello World";
var regex = /World/;
var index = str.indexOf(regex);
```
Keep in mind that the performance characteristics of these alternatives may vary depending on the specific implementation and environment.

In summary, the MeasureThat.net benchmark compares the performance of `indexOf` and `lastIndexOf`, highlighting the trade-offs between finding the first or last occurrence of a value within a string.

Related benchmarks:

index vs lastindexof empty (version: 0)

Comparing performance of: lastIndexOf vs indexOf

Created: 6 years ago by: Guest

Jump to the latest result

lastIndexOf

indexOf

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):