Benchmark: last number checker !

Script Preparation code:

var DEFAULT_COHORT_TEST_IDS = [0, 1, 2, 3, 4];
var DEFAULT_COHORT_TEST_IDS_STR = ['0', '1', '2', '3', '4'];
var getLastTokenOfString = (str) => {
  if (!str || typeof str !== 'string') return null;

  return str[str.length - 1];
};

Tests:

number list string slice
DEFAULT_COHORT_TEST_IDS.includes(Number('1234'.slice(-1)))
number list number divide
DEFAULT_COHORT_TEST_IDS.includes(Number('1234') & 10)
string list string indexing
DEFAULT_COHORT_TEST_IDS_STR.includes(getLastTokenOfString('1234'))

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
number list string slice
number list number divide
string list string indexing

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

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

LLMs can make mistakes. Check important info.

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

**Overview**

MeasureThat.net is a platform that allows users to create and run JavaScript microbenchmarks. The provided benchmark definition and test cases are used to measure the performance of various operations involving arrays, strings, and bitwise operators in JavaScript.

**Test Cases**

There are three individual test cases:

1. `number list string slice`: This test case checks if a specific element (the last digit of a number) is present in an array (`DEFAULT_COHORT_TEST_IDS`) using the `includes()` method.
2. `number list number divide`: This test case checks if a result of a division operation involving an array element and a constant value (`10`) is present in the same array (`DEFAULT_COHORT_TEST_IDS`).
3. `string list string indexing`: This test case checks if a specific character (the last digit of a string) is present in another array (`DEFAULT_COHORT_TEST_IDS_STR`) using the `includes()` method.

**Benchmark Definition and Script Preparation Code**

The benchmark definition JSON contains three fields:

* `Name`: The name of the benchmark.
* `Description`: An empty string, indicating no description for this benchmark.
* `Script Preparation Code`: A JavaScript code snippet that sets up variables and functions used in the test cases. Specifically:
	+ It defines an array `DEFAULT_COHORT_TEST_IDS` with five elements: `[0, 1, 2, 3, 4]`.
	+ It defines another array `DEFAULT_COHORT_TEST_IDS_STR` with the same elements as a string.
	+ It defines a function `getLastTokenOfString(str)` that extracts the last character from a given string. If the input is not a string or empty, it returns `null`.

**Options Compared**

The benchmark compares different approaches to perform operations involving arrays and strings:

1. Using `includes()` method with array elements.
2. Using bitwise operators (`&`) with array elements.

**Pros and Cons**

* **Includes() Method**:
	+ Pros: Efficient for checking membership in large arrays, easy to read and understand.
	+ Cons: May not be optimized for performance, can lead to false positives if the element is present in the array due to off-by-one errors or string padding.
* **Bitwise Operators**:
	+ Pros: Can potentially be faster for certain use cases, more compact code.
	+ Cons: May lead to unexpected results if not used carefully, can be less readable and maintainable.

**Library Usage**

The `getLastTokenOfString` function uses a standard JavaScript technique to extract the last character from a string. There is no third-party library involved in this specific example.

**Special JS Features or Syntax**

There are no special features or syntax used in this benchmark that would require additional explanation.

**Other Alternatives**

If you need to optimize these operations further, consider the following alternatives:

1. Use optimized `includes()` method implementations available in modern JavaScript engines.
2. Utilize native array and string methods like `findIndex()`, `findLastIndex()`, or `substr()` for more efficient results.
3. Consider using specialized libraries like `lodash` or `Array.prototype.at()` for more concise and readable code.

Keep in mind that the best approach depends on your specific use case, performance requirements, and personal preference as a developer.

Related benchmarks:

last number checker ! (version: 0)

Comparing performance of: number list string slice vs number list number divide vs string list string indexing

Created: 3 years ago by: Guest

Jump to the latest result

number list string slice

number list number divide

string list string indexing

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):