Benchmark: vanilla js replaceAll vs regex replace tabs to spaces

Tests:

replace regex
" \t asdf \t ".replace(/\t/g, " ");
replace All
" \t asdf \t ".replaceAll("\t", " ");

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
replace regex
replace All

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 7 months ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/140.0.0.0 Safari/537.36 Edg/140.0.0.0

Browser/OS: Chrome 140 on Windows

View result in a separate tab

Test name	Executions per second
replace regex	17690282.0 Ops/sec
replace All	12071906.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down what's being tested in the MeasureThat.net benchmark.

**Overview**

The benchmark compares two approaches to replace tabs (`\t`) with spaces in a string: using regular expressions (regex) and using a string method called `replaceAll`.

**Options compared**

Two options are compared:

1. **Replace using regex**: The `replace()` function is used, which takes three arguments: the value to be replaced, the replacement value, and an optional third argument for a global flag (g). In this case, `\t` is replaced with spaces (`"    "`).
2. **Replace using string method**: The `replaceAll()` function is used, which replaces all occurrences of a substring in a string.

**Pros and cons**

**Using regex:**

Pros:

* More flexible and powerful than string methods for replacing patterns.
* Can be used to replace other types of special characters or patterns.

Cons:

* Can be slower due to the complexity of parsing and matching patterns.
* May have performance issues with very large strings or complex patterns.

**Using string method (replaceAll):**

Pros:

* Often faster than regex, especially for simple replacements.
* More concise and easier to read than writing a custom regex function.

Cons:

* Limited flexibility and power compared to regex.
* Can only replace exact substrings, not patterns.

**Library/Language-specific features**

In this benchmark, no special JavaScript language or library-specific features are used. However, it's worth noting that MeasureThat.net often includes benchmarks for more advanced JavaScript features.

**Other alternatives**

If you're interested in replacing tabs with spaces in a string, you may also consider using the `replace()` function with a regular expression, but using the `g` flag to replace all occurrences:

```javascript
str.replace(/\t/g, '    ');
```

Alternatively, if you need more advanced text processing capabilities, you could use a library like `js-regex` or ` regex-string`.

**Benchmark preparation code**

The benchmark preparation code is not shown in this example, but it's likely that the code includes some setup or initialization to create the test string and set up the execution environment.

Overall, this benchmark provides a simple and straightforward way to compare the performance of two approaches to replacing tabs with spaces in a string: using regex versus using a string method like `replaceAll`.

Related benchmarks:

vanilla js replaceAll vs regex replace tabs to spaces (version: 0)

Comparing performance of: replace regex vs replace All

Created: 4 years ago by: Guest

Jump to the latest result

replace regex

replace All

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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