Benchmark: Removing whitespace: regex replace vs string trim vs regex match vs regex match global

Script Preparation code:

var string = '    fsajdf asdfjosa fjoiawejf oawjfoei jaosdjfsdjfo sfjos 2324234 sdf safjao j o        sdlfks dflks l      '

Tests:

regex replace
string.replace(/^\s+|\s+$|\s+(?=\s)/g, '')
trim
string.trim()
regex match
string.match(/(\S.+\S)/)[1]
regex match global
string.match(/(\S.+\S)/g)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
regex replace
trim
regex match
regex match global

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 3 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36

Browser/OS: Chrome 97 on Windows

View result in a separate tab

Test name	Executions per second
regex replace	1916148.2 Ops/sec
trim	9932945.0 Ops/sec
regex match	3840764.0 Ops/sec
regex match global	3378723.8 Ops/sec

Autogenerated LLM Summary (model llama3.2:3b, generated 6 months ago):

LLMs can make mistakes. Check important info.

Let's dive into the benchmark and explain what's being tested.

**What is being tested?**

The provided JSON represents a JavaScript microbenchmark that tests four different approaches to remove whitespace from a string:

1. `string.replace()` with regular expression (regex) patterns to match beginning, end, or interior whitespace.
2. `string.trim()`, which removes whitespace from the start and end of a string by default.

Additionally, there are two regex-based approaches being tested:

3. `string.match()` followed by indexing into the matched array (`[1]`) to extract the non-whitespace part of the string.
4. `string.match()` with the global flag (`g`) enabled to match whitespace across multiple occurrences in the string.

**Options compared:**

* The test cases compare different methods for removing or extracting non-whitespace characters from a string:
	+ Regular expression-based approaches (regex replace, regex match, and regex match global).
	+ String trimming method (`string.trim()`).

**Pros and Cons of each approach:**

1. **Regex Replace**: This method uses regular expressions to match and remove whitespace patterns. Pros: can handle complex whitespace patterns, flexible. Cons:
	* Can be slower due to the overhead of compiling and executing regex patterns.
	* May not work as expected with non-standard or edge cases.
2. **String Trim**: This method simply removes whitespace characters from the start and end of a string. Pros: fast, simple, reliable. Cons:
	+ Only works for basic whitespace trimming (not suitable for complex cases).
	+ Does not preserve whitespace characters within the string.
3. **Regex Match with Indexing**: This approach matches whitespace characters using regex and then extracts the non-whitespace part by indexing into the matched array. Pros: allows direct access to non-whitespace parts, flexible. Cons:
	* Requires an additional step (indexing) to extract the desired result, which may introduce overhead.
	+ May not work correctly if the regex pattern is complex or has multiple capture groups.
4. **Regex Match Global**: This approach uses the global flag (`g`) with regex to match whitespace across multiple occurrences in a string. Pros: handles multi-occurrence patterns more efficiently than `string.replace()`. Cons:
	* Can be slower due to the overhead of compiling and executing regex patterns with global flags.
	+ May not work correctly if the regex pattern is complex or has multiple capture groups.

**Library and syntax used:**

The benchmark uses JavaScript's built-in string methods (`replace()`, `trim()`) and regular expression capabilities. No external libraries are required.

**Special JS features or syntax:**

This benchmark does not explicitly use any special JavaScript features or syntax beyond standard regex patterns. However, the use of async programming (in a hypothetical context where these benchmarks were executed concurrently) may be influenced by JavaScript's asynchronous nature.

**Alternatives:**

Other approaches for removing whitespace from strings might include:

* Using other string manipulation libraries (e.g., String.prototype.split(), String.prototype.join()) or frameworks.
* Employing custom algorithms that handle specific edge cases or performance optimizations.

Related benchmarks:

Removing whitespace: regex replace vs string trim vs regex match vs regex match global (version: 1)

testing removing beginning and end whitespace

Comparing performance of: regex replace vs trim vs regex match vs regex match global

Created: 3 years ago by: Registered User

Jump to the latest result

regex replace

trim

regex match

regex match global

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 6 months ago):