Benchmark: Length vs regex - MeasureThat.net

Script Preparation code:

var objectIdRegexp = /^[a-f\d]{24}$/;
var input = "abcd1234";

Tests:

Pure regex
objectIdRegexp.test(input);
STR leng
input.length === 24 && objectIdRegexp.test(input)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Pure regex
STR leng

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 break down the provided JSON benchmark definition and explain what's being tested.

**Benchmark Definition**

The benchmark is defined by two test cases:

1. **"Pure regex"`**: This test case measures the execution time of the `objectIdRegexp.test(input)` function, where `objectIdRegexp` is a regular expression object created from a hexadecimal string (`"[a-f\\d]{24}$"`) and `input` is set to `"abcd1234"`.
2. **"STR leng"`**: This test case measures the execution time of the comparison `input.length === 24 && objectIdRegexp.test(input)`. Here, `input` is still set to `"abcd1234"`.

**Options Compared**

In this benchmark, we have two options being compared:

* The "Pure regex" approach: uses only the regular expression object (`objectIdRegexp`) and directly tests its `test()` method on the input string.
* The "STR leng" approach: uses a more conventional JavaScript way to compare the length of the input string with 24 and then tests the regular expression object's `test()` method.

**Pros and Cons**

**Pure regex approach:**

Pros:

* This approach is straightforward and directly measures the performance of the regular expression engine.
* It might be more accurate for measuring pure regex performance, as it eliminates any overhead from additional comparisons or operations.

Cons:

* If the regular expression engine is slow due to complex patterns or optimizations, this approach may not accurately represent its true performance capabilities.
* This approach requires a good understanding of regular expressions and their performance characteristics.

**STR leng approach:**

Pros:

* This approach is more representative of real-world use cases, where strings are often compared to lengths before being processed by regex engines.
* It allows for a more comprehensive understanding of the overall pipeline's performance, including any additional overhead from string comparisons.

Cons:

* This approach introduces extra operations and comparisons that might not be directly related to the regular expression engine's performance.
* If the comparison is fast enough, it may dominate the benchmark results and obscure the true performance characteristics of the regex engine.

**Library: `objectIdRegexp`**

The `objectIdRegexp` object is a custom-built regular expression pattern designed to test for hexadecimal strings with 24 characters. The purpose of this library is to provide a specific test case that targets the performance of the regular expression engine on such patterns.

**Special JS Feature or Syntax**

There are no special JavaScript features or syntax mentioned in the provided benchmark definition.

**Alternatives**

Other alternatives for testing the performance of regular expressions could include:

* Testing a variety of pattern types, such as word boundaries, character classes, or repetition patterns.
* Using different input strings with varying lengths and complexities.
* Comparing the performance of regular expression engines from different browsers or versions.
* Incorporating additional overhead, such as processing large datasets or concurrent execution.

Keep in mind that each alternative might require adjustments to the benchmark definition and test cases to ensure accurate and representative results.

Related benchmarks:

Length vs regex (version: 0)

Comparing performance of: Pure regex vs STR leng

Created: 2 years ago by: Guest

Jump to the latest result

Pure regex

STR leng

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):