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undefined tests
(version: 0)
Comparing performance of:
typeof false !== "undefined" vs false !== undefined
Created:
2 years ago
by:
Registered User
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Tests:
typeof false !== "undefined"
typeof false !== "undefined"
false !== undefined
false !== undefined
Rendered benchmark preparation results:
Suite status:
<idle, ready to run>
Run tests (2)
Previous results
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Test case name
Result
typeof false !== "undefined"
false !== undefined
Fastest:
N/A
Slowest:
N/A
Latest run results:
Run details:
(Test run date:
2 years ago
)
User agent:
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/122.0.0.0 Safari/537.36
Browser/OS:
Chrome 122 on Windows
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<iframe src="https://measurethat.net/Embed?id=508045" width="100%" height="500px"></iframe>
Test name
Executions per second
typeof false !== "undefined"
237677616.0 Ops/sec
false !== undefined
18702544.0 Ops/sec
Autogenerated LLM Summary
(model
llama3.2:3b
, generated one year ago):
Let's break down the provided benchmark and its test cases. **Benchmark Purpose** The benchmark measures the performance difference between two JavaScript expressions: `typeof false !== "undefined"` and `false !== undefined`. The purpose of this benchmark is to compare how fast each expression can be evaluated in different browsers. **Options Compared** There are only two options being compared: 1. `typeof false !== "undefined"` 2. `false !== undefined` **Pros and Cons of Each Approach** **1. Using `typeof`** * Pros: + More explicit and clear code + Easier to read and maintain * Cons: + May be slower due to the need to look up the type of a variable using `typeof` + Some browsers may optimize this check, making it faster **2. Without `typeof`** * Pros: + Can be faster since there's no lookup required for variable types + May be less optimized by some browsers * Cons: + Less explicit and more ambiguous code (it's not immediately clear what the expression is doing) + Requires careful consideration of the type of the `false` value **Library Used** There isn't a specific library mentioned in the provided benchmark. However, `typeof` is a built-in JavaScript operator that returns the type of a variable. **Special JS Features or Syntax** No special features or syntax are being used in this benchmark. **Other Alternatives** If you were to rewrite this benchmark, alternative options might include: * Using a more modern approach with arrow functions and template literals (e.g., `false?.toString() !== undefined`) * Comparing different comparison operators (e.g., `===`, `!=`, etc.) * Adding additional variables or conditions to the expressions Keep in mind that any changes to the benchmark would need to be thoroughly tested to ensure accurate results. **Benchmark Preparation Code** The provided "Script Preparation Code" and "Html Preparation Code" fields are empty, suggesting that this benchmark does not require any setup code beyond what's included in the `Benchmark Definition` JSON.
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