Benchmark: typeof raw string vs const

Script Preparation code:

var fn = () => {};
var TYPEOF_FN = "function";

Tests:

raw
typeof fn === "function"
const
typeof fn === TYPEOF_FN

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
raw
const

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:131.0) Gecko/20100101 Firefox/131.0

Browser/OS: Firefox 131 on Linux

View result in a separate tab

Test name	Executions per second
raw	810855168.0 Ops/sec
const	761873408.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Measuring the performance of JavaScript benchmarks is crucial for understanding how different languages and browsers execute code.

The provided JSON represents a simple benchmark that tests two approaches to defining variables in JavaScript:

1. **Raw String**: This approach uses a raw string literal, where the variable `TYPEOF_FN` is defined as `"function"`. The variable `fn` is then declared with this value.
2. **Constant Declaration**: This approach uses the `const` keyword to declare a constant variable `TYPEOF_FN`, which is also set to `"function"`.

**Options Comparison**

Both approaches have their pros and cons:

* **Raw String**:
	+ Pros: No additional overhead due to type checking or const declaration.
	+ Cons: The variable name "fn" might not be as readable, and it's easier to accidentally change the value of TYPEOF_FN.
* **Constant Declaration** (using `const`):
	+ Pros: More readable code, with explicit intent that TYPEOF_FN should not be changed. Additionally, modern browsers will optimize constant expressions.
	+ Cons: There is a slight overhead due to type checking and constant declaration.

Another consideration for this benchmark is the use of the **typeof** operator. The `typeof` operator in JavaScript returns the type of its operand as a string. In this case, it's used to compare the value of `fn` with `"function"`. This approach allows us to test how different browsers and engines handle the `typeof` operator.

**Library and Special JS Features**

There are no explicit libraries or special JS features used in this benchmark. However, it does rely on a few browser-specific features:

* **const declaration**: Modern JavaScript engines (like those in Firefox) optimize constant expressions.
* **TypeOf operator**: The `typeof` operator is available in most modern JavaScript environments.

**Other Alternatives**

To test similar benchmarks, you could consider the following alternatives:

1. Test using `let` instead of `var`: This would allow us to explore how different browsers and engines handle variable declarations with `let`.
2. Use a larger scope for the variables: For example, testing if the value of `fn` can be changed outside its scope.
3. Explore performance differences between different JavaScript engine versions or architectures (e.g., WebAssembly).
4. Include additional test cases that cover different scenarios, such as:
	* Using template literals instead of raw strings.
	* Testing with other data types (e.g., numbers, booleans).
	* Evaluating the impact of tree shaking on performance.

Keep in mind that benchmarking JavaScript code is a complex task and may require careful consideration of various factors to ensure accurate results.

Related benchmarks:

typeof raw string vs const (version: 0)

Comparing performance of: raw vs const

Created: one year ago by: Guest

Jump to the latest result

raw

const

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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