Benchmark: Capitalize - MeasureThat.net

Tests:

1
function capitalizeFirstLetter(string) { return string[0].toUpperCase() + string.slice(1); } capitalizeFirstLetter('string');
2
function capitalizeFirstLetter(s) { return s[0].toUpperCase() + s.substr(1); } capitalizeFirstLetter('string');
3
function capitalizeFirstLetter(s) { s.replace(s[0], s[0].toUpperCase()); } capitalizeFirstLetter('string');

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
1
2
3

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 4 months ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/85.0.4183.127 Safari/537.36 OPR/60.3.3004.55692

Browser/OS: Opera 60 on Linux

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Test name	Executions per second
1	6713478.5 Ops/sec
2	7144399.0 Ops/sec
3	295866.3 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript benchmarking on MeasureThat.net.

**Benchmark Definition JSON**

The provided Benchmark Definition JSON represents a simple JavaScript function that capitalizes the first letter of a given string. The definition includes three different implementations:

1. `capitalizeFirstLetter(string) { return string[0].toUpperCase() + string.slice(1); }`
2. `capitalizeFirstLetter(s) { return s[0].toUpperCase() + s.substr(1); }`
3. `capitalizeFirstLetter(s) { s.replace(s[0], s[0].toUpperCase()); }`

These implementations differ in their approach to capitalizing the first letter of the input string.

**Options Comparison**

The three implementations compared are:

1. **String slicing**: The first implementation uses `string.slice(1)` to extract the substring starting from the second character, and then concatenates it with the uppercase first character using `toUpperCase()`.
2. **String substr**: The second implementation uses `s.substr(1)` to achieve the same result as string slicing.
3. **String replacement**: The third implementation uses the `replace()` method to replace the first character of the input string with its uppercase equivalent.

**Pros and Cons**

Here's a brief summary of the pros and cons of each approach:

* **String Slicing (1)**:
	+ Pros: Simple, efficient, and concise.
	+ Cons: May not work as expected for non-ASCII characters or strings containing newline characters.
* **String Substr (2)**:
	+ Pros: Similar to string slicing, but with a slightly different syntax.
	+ Cons: May not be as efficient due to the use of `substr()` method, which can lead to slower execution times.
* **String Replacement (3)**:
	+ Pros: Works well for all types of strings, including non-ASCII characters and newline characters.
	+ Cons: Can be less efficient than string slicing or substr due to the overhead of the `replace()` method.

**Library Usage**

None of the implementations use any external libraries. However, it's worth noting that some JavaScript engines may provide additional optimizations or features for certain strings, such as Unicode support.

**Special JS Feature/Syntax**

There are no special JavaScript features or syntax used in these examples. The focus is on simple string manipulation and optimization techniques.

**Other Alternatives**

If you're interested in exploring alternative approaches, here are a few options:

* **Regex**: You could use regular expressions to capitalize the first letter of the input string.
* **String method**: Some JavaScript engines provide additional string methods that can be used for this purpose, such as `toUpperCase()` and `slice()`.
* **Built-in functions**: Modern JavaScript provides built-in functions like `String.prototype.charAt()` and `String.prototype.toUpperCase()` that can be used to achieve similar results.

Keep in mind that the choice of approach ultimately depends on your specific use case, performance requirements, and personal preference.

Related benchmarks:

Capitalize (version: 0)

Comparing performance of: 1 vs 2 vs 3

Created: 8 years ago by: Guest

Jump to the latest result

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2

3

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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