Benchmark: RegEx.test vs. String.match vs. String.search

Script Preparation code:

var string = "Hello world!";
var regex = /Hello/;

Tests:

RegEx.test
regex.test(string);
String.match
string.match(regex);
Strin.search
string.search(regex)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
RegEx.test
String.match
Strin.search

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.11; rv:78.0) Gecko/20100101 Firefox/78.0

Browser/OS: Firefox 78 on Mac OS X 10.11

View result in a separate tab

Test name	Executions per second
RegEx.test	3833048.5 Ops/sec
String.match	1656165.5 Ops/sec
Strin.search	3855165.8 Ops/sec

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

LLMs can make mistakes. Check important info.

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

**Benchmark Definition**

The benchmark is designed to compare the performance of three different approaches for searching a regular expression (Regex) in a string:

1. `regex.test(string)`: This method tests whether the string matches the regular expression.
2. `string.match(regex)`: This method returns an array of strings if the string matches the regular expression, or null otherwise.
3. `string.search(regex)`: This method searches for the first occurrence of the regular expression in the string and returns the index of the match, or -1 if no match is found.

**Options Compared**

The three methods are compared on a single input:

* The regular expression: `/Hello/`
* The input string: `"Hello world!"`

**Pros and Cons of Each Approach**

1. `regex.test(string)`:
	* Pros: Simple, easy to understand, and efficient for exact matches.
	* Cons: May not be suitable for more complex patterns or multiple matches.
2. `string.match(regex)`:
	* Pros: Can handle multiple matches, but may have a higher overhead due to the array creation.
	* Cons: Returns an array of strings, which can be slower than a single index value.
3. `string.search(regex)`:
	* Pros: Fast and efficient for exact matches, with minimal overhead.
	* Cons: May return -1 if no match is found, requiring additional checks.

**Library Used**

None explicitly mentioned in the benchmark definition.

**Special JS Feature/Syntax**

The regular expression `/Hello/` uses a positive lookahead assertion (`(?=...)`) which is not relevant to the benchmark's purpose. This feature allows for matching strings that contain "Hello" without capturing it as a group.

**Other Considerations**

* The benchmark only tests exact matches, ignoring cases where the string contains "hello" (with lowercase 'h') or other variations.
* No error handling is performed; if the regular expression is invalid, the program may throw an exception.

**Alternative Approaches**

For more complex patterns, you might consider using:

1. `string.replace(regex, replacement)`: Replaces all occurrences of the pattern with a specified value.
2. `Array.prototype.forEach()`: Iterates over the matches returned by `string.match(regex)` and performs actions on each match.
3. Other libraries or modules like RegEx or String-Patterns for more advanced features.

In summary, this benchmark is designed to compare the performance of three different approaches for searching a regular expression in a string. It highlights the trade-offs between simplicity, efficiency, and handling multiple matches.

Related benchmarks:

RegEx.test vs. String.match vs. String.search (version: 0)

Comparing performance of: RegEx.test vs String.match vs Strin.search

Created: 3 years ago by: Guest

Jump to the latest result

RegEx.test

String.match

Strin.search

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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