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string functions
(version: 0)
Comparing performance of:
a vs b vs c
Created:
5 years ago
by:
Guest
Jump to the latest result
Script Preparation code:
const myStr = '!foo bar baz'; const noop = Function.prototype;
Tests:
a
const myStr = '!foo bar baz'; const noop = Function.prototype; if (myStr[0] === '!') noop();
b
const myStr = '!foo bar baz'; const noop = Function.prototype; if (myStr.charAt(0) === '!') noop();
c
const myStr = '!foo bar baz'; const noop = Function.prototype; if (myStr.startsWith('!')) noop();
Rendered benchmark preparation results:
Suite status:
<idle, ready to run>
Run tests (3)
Previous results
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Test case name
Result
a
b
c
Fastest:
N/A
Slowest:
N/A
Latest run results:
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Autogenerated LLM Summary
(model
llama3.2:3b
, generated one year ago):
Measuring JavaScript performance is a fascinating topic, and MeatingThat.net provides a great platform for doing so. **What is tested on the provided JSON?** The provided JSON represents a set of benchmark tests for string functions in JavaScript. The tests are designed to measure the performance of different string manipulation methods in JavaScript. **Options compared:** There are three options compared: 1. **String indexing using square brackets (`[]`)** (Test Case "a") 2. **String indexing using `charAt()`** (Test Case "b") 3. **String matching using `startsWith()`** (Test Case "c") **Pros and Cons of each approach:** * **String indexing using square brackets (`[]`)**: + Pros: Fast and efficient, especially for modern browsers. + Cons: May not work as expected in older browsers or with certain string types. * **String indexing using `charAt()`**: + Pros: Widely supported across browsers, including older ones. + Cons: Generally slower than square bracket indexing. * **String matching using `startsWith()`**: + Pros: Convenient and easy to read, especially for simple patterns. + Cons: May be slower than other methods due to the regex engine's overhead. **Library usage:** There is no library explicitly used in these tests. However, the use of `Function.prototype` suggests that the test might be targeting a specific JavaScript version or browser implementation where this syntax is supported. **Special JS feature/syntax:** The use of `Function.prototype` and the `noop()` function indicate that this test might be targeting a modern JavaScript environment (ECMAScript 2015+). The use of template literals (`''`) for string interpolation is also compatible with modern browsers, but may not work in older versions. **Other alternatives:** If these tests were to be run on other platforms or with different JavaScript implementations, alternative methods might be used. For example: * On mobile devices or Internet Explorer, the `charAt()` method might be preferred due to its wider support. * In Node.js environments, the use of the `String.prototype.startsWith()` method (introduced in ECMAScript 2015) might be more suitable. **Benchmark preparation code and individual test cases:** The provided benchmark preparation code sets up a simple string variable (`myStr`) and creates a no-op function using `Function.prototype`. The individual test cases then use different string manipulation methods to execute the no-op function. The test cases are designed to demonstrate the performance differences between these methods. **Benchmark result interpretation:** The benchmark results show the number of executions per second for each test case on a Windows desktop with Firefox 84 browser. The raw UA string and other metadata provide additional context about the testing environment. By comparing the execution speeds, users can determine which string manipulation method is most suitable for their specific use cases.
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