Benchmark: .startsWith() vs .test() vs .match() vs .indexOf() (correct)

Script Preparation code:

var html = "https://www.google.com";

Tests:

regexp .test()
/^https?:\/\//.test(html)
string .match()
!!html.match(/^https:\/\//)
indexOf === 0
html.indexOf('https://') === 0
string .startsWith()
html.startsWith('https://')

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
regexp .test()
string .match()
indexOf === 0
string .startsWith()

Fastest: N/A

Slowest: N/A

Latest run results:

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

LLMs can make mistakes. Check important info.

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

**Benchmark Description**
The benchmark compares four different methods to check if a string starts with a specific substring or matches a regular expression:

1. `.startsWith()`: checks if the string starts with the specified substring.
2. `.test()`: tests if the string passes a given regular expression.
3. `String.prototype.match()` (or `.match()`: attempts to find a match for the regular expression in the string, returning an array of matches or null if no match is found.
4. `indexOf() === 0`: checks if the index of the specified substring in the original string is 0.

**Options Comparison**

* **.startsWith():**
	+ Pros: Simple, efficient, and widely supported by browsers.
	+ Cons: Not as flexible as regular expressions, may not work correctly with non-ASCII strings or Unicode characters.
* **.test():**
	+ Pros: Highly flexible and powerful for regular expression matching, can be used in a variety of contexts.
	+ Cons: May have performance overhead compared to simple string checks, less widely supported by older browsers.
* **String.prototype.match():**
	+ Pros: Can be more flexible than .startsWith(), but still relatively straightforward to use.
	+ Cons: Returns an array of matches or null, which can lead to extra processing and checks.
* **indexOf === 0:**
	+ Pros: Simple, fast, and widely supported by browsers. However, it may not work correctly with non-ASCII strings or Unicode characters.

**Library Usage**

None of the benchmark test cases use external libraries for their methods. The built-in `.startsWith()`, `String.prototype.match()`, and `indexOf()` methods are used as-is in the tests.

**Special JavaScript Features/Syntax**
No special JavaScript features or syntax is being tested in this benchmark. All the test cases are standard, widely-supported JavaScript code snippets.

**Alternatives**

If you need to write a similar benchmark, consider exploring other methods, such as:

* Using `RegExp.test()` instead of `.test()`
* Employing more advanced regular expression techniques, like lazy matching (`.*?`) or possessive quantifiers (`++`)
* Implementing custom string comparison functions
* Leveraging browser-specific optimizations or APIs (e.g., Chrome's `String.prototype.startsWith()`)

Keep in mind that each method has its trade-offs and performance characteristics.

Related benchmarks:

.startsWith() vs .test() vs .match() vs .indexOf() (correct) (version: 0)

Comparing performance of: regexp .test() vs string .match() vs indexOf === 0 vs string .startsWith()

Created: 4 years ago by: Guest

Jump to the latest result

regexp .test()

string .match()

indexOf === 0

string .startsWith()

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):