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Object property check bool cast !! vs plain call
(version: 0)
Comparing performance of:
Bool cast !! vs Plain call
Created:
5 years ago
by:
Guest
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Script Preparation code:
killer = {killed: []}
Tests:
Bool cast !!
if (!!killer.killed) console.log(1); else console.log(2); if (!!killer.killedby) console.log(1); else console.log(2);
Plain call
if (killer.killed) console.log(1); else console.log(2); if (killer.killedby) console.log(1); else console.log(2);
Rendered benchmark preparation results:
Suite status:
<idle, ready to run>
Run tests (2)
Previous results
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Test case name
Result
Bool cast !!
Plain call
Fastest:
N/A
Slowest:
N/A
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Autogenerated LLM Summary
(model
llama3.2:3b
, generated one year ago):
Let's break down the provided benchmark and explain what's being tested, compared, and some considerations. **Benchmark Overview** The test case is designed to compare two approaches for checking if an object property exists: using double negation (`!!`) versus calling the property directly. **Options Compared** There are two options being compared: 1. **Bool cast !!**: This approach uses the `!!` operator, which is a common idiom in JavaScript to coerce a value to a boolean. It checks if the value is truthy or falsy by negating it twice. 2. **Plain call**: This approach calls the property directly without any additional operators. **Pros and Cons** * **Bool cast !!**: + Pros: This approach can be more readable and concise, as it uses a single operator to achieve the same result. + Cons: Some developers might find this idiom confusing, especially for those new to JavaScript. Additionally, if the property is not an object or does not have a `valueOf` method, `!!` will return `true`. * **Plain call**: + Pros: This approach can be more explicit and easier to understand for some developers, as it clearly states what's being done. + Cons: It might require more code or syntax, making it less concise. **Library Usage** There is no specific library mentioned in the provided benchmark. However, note that `killer` is an object defined using the bracket notation (`{killed: []}`), which is a common way to create objects in JavaScript. **Special JS Feature/Syntax (None)** Since neither of the test cases uses any special JavaScript features or syntax beyond what's standard, this part can be considered null for both tests. **Other Alternatives** Some alternative approaches could include: * Using `in` operator: `if ('killed' in killer) console.log(1);` * Using optional chaining (`?.`) (introduced in ECMAScript 2020): `if (killer.killed?.length > 0) console.log(1);` * Using a simple property check with `typeof`: `if (typeof killer === 'object') if (killer.killed) console.log(1);` Keep in mind that the choice of approach depends on personal preference, coding style, and specific use cases. I hope this explanation helps!
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double-bang-vs-boolean-vs-unfedined-cast
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