Benchmark: repeat - MeasureThat.net

Script Preparation code:

function repeatify(string, repetitions) {
   if (repetitions < 0 || repetitions === Infinity) {
      throw new RangeError('Invalid repetitions number');
   }
 
   let result = '';
 
   for (let i = 0; i < repetitions; i++) {
      result += string;
   }
 
   return result;
}

function repeatifyWithArrayAndJoin(string, repetitions) {
   if (repetitions < 0 || repetitions === Infinity) {
      throw new RangeError('Invalid repetitions number');
   }
 
   const result = [];
 
   for (let i = 0; i < repetitions; i++) {
      result.push(string);
   }
 
   return result.join('');
}

function repeatifyWithNewArray(string, repetitions) {
   if (repetitions < 0 || repetitions === Infinity) {
      throw new RangeError('Invalid repetitions number');
   }
  
   return new Array(repetitions).join(string);
}

function _checkRepeations(repetitions) {
	if (repetitions < 0 || repetitions === Infinity) {
      throw new RangeError('Invalid repetitions number');
   }
}

function repeatifyWithNewArrayAndExternalThrow(string, repetitions) {
   _checkRepeations(repetitions);
  
   return new Array(repetitions).join(string);
}

function repeatifyWithNewArrayAndExternalThrowWithProps(string, repetitions) {
   this.checkRepeations(repetitions);
  
   return new this.Array(repetitions).join(string);
}

var ctx = {
	checkRepeations: _checkRepeations,
  	Array: Array
}

repeatifyWithNewArrayAndExternalThrowWithProps = repeatifyWithNewArrayAndExternalThrowWithProps.bind(ctx);

var TEST_STRING = 'home, sweet home';
var COUNT = 1e6;

​x
 
function repeatify(string, repetitions) {   if (repetitions < 0 || repetitions === Infinity) {      throw new RangeError('Invalid repetitions number');   }    let result = '';    for (let i = 0; i < repetitions; i++) {      result += string;   }    return result;}​function repeatifyWithArrayAndJoin(string, repetitions) {   if (repetitions < 0 || repetitions === Infinity) {      throw new RangeError('Invalid repetitions number');   }    const result = [];    for (let i = 0; i < repetitions; i++) {      result.push(string);   }    return result.join('');}​function repeatifyWithNewArray(string, repetitions) {   if (repetitions < 0 || repetitions === Infinity) {      throw new RangeError('Invalid repetitions number');   }     return new Array(repetitions).join(string);}​function _checkRepeations(repetitions) {    if (repetitions < 0 || repetitions === Infinity) {      throw new RangeError('Invalid repetitions number');   }}​function repeatifyWithNewArrayAndExternalThrow(string, repetitions) {   _checkRepeations(repetitions);     return new Array(repetitions).join(string);}​function repeatifyWithNewArrayAndExternalThrowWithProps(string, repetitions) {   this.checkRepeations(repetitions);     return new this.Array(repetitions).join(string);}​var ctx = {    checkRepeations: _checkRepeations,    Array: Array}​repeatifyWithNewArrayAndExternalThrowWithProps = repeatifyWithNewArrayAndExternalThrowWithProps.bind(ctx);​var TEST_STRING = 'home, sweet home';var COUNT = 1e6;

Tests:

native repeat
TEST_STRING.repeat(COUNT);
TEST_STRING.repeat(COUNT);
stupid repeatify
repeatify(TEST_STRING, COUNT);
repeatify(TEST_STRING, COUNT);
repeatifyWithArrayAndJoin
repeatifyWithArrayAndJoin(TEST_STRING, COUNT);
repeatifyWithArrayAndJoin(TEST_STRING, COUNT);
repeatifyWithNewArray
repeatifyWithNewArray(TEST_STRING, COUNT);
repeatifyWithNewArray(TEST_STRING, COUNT);
repeatifyWithNewArrayAndExternalThrow
repeatifyWithNewArrayAndExternalThrow(TEST_STRING, COUNT);
repeatifyWithNewArrayAndExternalThrow(TEST_STRING, COUNT);
repeatifyWithNewArrayAndExternalThrowWithProps
repeatifyWithNewArrayAndExternalThrowWithProps(TEST_STRING, COUNT);
repeatifyWithNewArrayAndExternalThrowWithProps(TEST_STRING, COUNT);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Experimental features:

Memory measurements supported only in Chrome.
For precise memory measurements Chrome must be launched with --enable-precise-memory-info flag.
More information: Monitoring JavaScript Memory

Test case name	Result
native repeat
stupid repeatify
repeatifyWithArrayAndJoin
repeatifyWithNewArray
repeatifyWithNewArrayAndExternalThrow
repeatifyWithNewArrayAndExternalThrowWithProps

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 8 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/57.0.2952.0 Safari/537.36

Browser/OS: Chrome 57 on Mac OS X 10.11.6

View result in a separate tab

Test name	Executions per second
native repeat	2025898.0 Ops/sec
stupid repeatify	10.2 Ops/sec
repeatifyWithArrayAndJoin	12.5 Ops/sec
repeatifyWithNewArray	58.9 Ops/sec
repeatifyWithNewArrayAndExternalThrow	60.6 Ops/sec
repeatifyWithNewArrayAndExternalThrowWithProps	61.8 Ops/sec

Autogenerated LLM Summary (model llama3.2:3b, generated 4 months ago):

Taking a deep breath...

Measuring JavaScript performance is crucial, and MeasureThat.net provides a great platform for benchmarking various approaches.

Benchmark Definition JSON

The provided Benchmark Definition JSON defines a simple string repetition task. The script preparation code consists of four different implementations of the repeatify function with varying levels of complexity:

native repeat: Uses the built-in string multiplication operator (*) to repeat the input string.
stupid repeatify: A naive implementation that uses a loop to concatenate strings.
repeatifyWithArrayAndJoin: Utilizes an array and the join() method to repeat the input string.
repeatifyWithNewArray: Creates a new array with repeated elements using the new Array(repetitions) constructor.
repeatifyWithNewArrayAndExternalThrow: Similar to the previous implementation, but uses an external function to throw an error for invalid repetitions.

Individual Test Cases

Each test case corresponds to one of the above implementations, with a unique name:

native repeat: The built-in string multiplication operator approach.
stupid repeatify: A simple loop-based concatenation implementation.
repeatifyWithArrayAndJoin: Uses an array and join() for repetition.
repeatifyWithNewArray: Creates a new array with repeated elements.
repeatifyWithNewArrayAndExternalThrow: Similar to the previous implementation, but uses an external function.

Benchmark Results

The latest benchmark results show the performance of each test case across different devices and browsers. The results are expressed in executions per second (ExecutionsPerSecond).

Pros and Cons

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

native repeat: Fast, built-in functionality. However, it may not be as flexible or efficient for larger repetition counts.
stupid repeatify: Simple to implement but can lead to performance issues with large input strings due to string concatenation overhead.
repeatifyWithArrayAndJoin: Efficient and scalable, using array operations under the hood. However, it may have a slight performance hit compared to native repeat.
repeatifyWithNewArray: Creates a new array for each repetition, leading to memory allocation and deallocation overhead. This approach can be less efficient than others.

Recommendations

Based on the benchmark results, repeatifyWithArrayAndJoin appears to be the most efficient implementation, offering a good balance between performance and scalability. However, the built-in string multiplication operator (native repeat) remains a close second.

When choosing an implementation for your specific use case, consider factors such as:

Repetition count: For small repetition counts, native repeat might be sufficient.
Input size: Larger input strings may benefit from more efficient approaches like repeatifyWithArrayAndJoin.
Performance requirements: If you need the best possible performance, repeatifyWithArrayAndJoin is a good choice.

Keep in mind that these are general guidelines, and the optimal approach may vary depending on your specific requirements.

LLMs can make mistakes. Check important info.

Taking a deep breath...

Measuring JavaScript performance is crucial, and MeasureThat.net provides a great platform for benchmarking various approaches.

**Benchmark Definition JSON**

The provided Benchmark Definition JSON defines a simple string repetition task. The script preparation code consists of four different implementations of the `repeatify` function with varying levels of complexity:

1.  **native repeat**: Uses the built-in string multiplication operator (`*`) to repeat the input string.
2.  **stupid repeatify**: A naive implementation that uses a loop to concatenate strings.
3.  **repeatifyWithArrayAndJoin**: Utilizes an array and the `join()` method to repeat the input string.
4.  **repeatifyWithNewArray**: Creates a new array with repeated elements using the `new Array(repetitions)` constructor.
5.  **repeatifyWithNewArrayAndExternalThrow**: Similar to the previous implementation, but uses an external function to throw an error for invalid repetitions.

**Individual Test Cases**

Each test case corresponds to one of the above implementations, with a unique name:

1.  `native repeat`: The built-in string multiplication operator approach.
2.  `stupid repeatify`: A simple loop-based concatenation implementation.
3.  `repeatifyWithArrayAndJoin`: Uses an array and `join()` for repetition.
4.  `repeatifyWithNewArray`: Creates a new array with repeated elements.
5.  `repeatifyWithNewArrayAndExternalThrow`: Similar to the previous implementation, but uses an external function.

**Benchmark Results**

The latest benchmark results show the performance of each test case across different devices and browsers. The results are expressed in executions per second (`ExecutionsPerSecond`).

**Pros and Cons**

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

1.  **native repeat**: Fast, built-in functionality. However, it may not be as flexible or efficient for larger repetition counts.
2.  `stupid repeatify`: Simple to implement but can lead to performance issues with large input strings due to string concatenation overhead.
3.  `repeatifyWithArrayAndJoin`: Efficient and scalable, using array operations under the hood. However, it may have a slight performance hit compared to native repeat.
4.  `repeatifyWithNewArray`: Creates a new array for each repetition, leading to memory allocation and deallocation overhead. This approach can be less efficient than others.

**Recommendations**

Based on the benchmark results, `repeatifyWithArrayAndJoin` appears to be the most efficient implementation, offering a good balance between performance and scalability. However, the built-in string multiplication operator (`native repeat`) remains a close second.

When choosing an implementation for your specific use case, consider factors such as:

*   Repetition count: For small repetition counts, `native repeat` might be sufficient.
*   Input size: Larger input strings may benefit from more efficient approaches like `repeatifyWithArrayAndJoin`.
*   Performance requirements: If you need the best possible performance, `repeatifyWithArrayAndJoin` is a good choice.

Keep in mind that these are general guidelines, and the optimal approach may vary depending on your specific requirements.

Related benchmarks:

repeat (version: 4)

Comparing performance of: native repeat vs stupid repeatify vs repeatifyWithArrayAndJoin vs repeatifyWithNewArray vs repeatifyWithNewArrayAndExternalThrow vs repeatifyWithNewArrayAndExternalThrowWithProps

Created: 8 years ago by: Registered User

Jump to the latest result

native repeat

stupid repeatify

repeatifyWithArrayAndJoin

repeatifyWithNewArray

repeatifyWithNewArrayAndExternalThrow

repeatifyWithNewArrayAndExternalThrowWithProps

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 4 months ago):