Benchmark: Normal vs ?. - MeasureThat.net

Script Preparation code:

function mitt(e) {
    return {
        all: e = e || new Map,
        on: function(n, t) {
            var f = e.get(n);
            f ? f.push(t) : e.set(n, [t])
        },
        off: function(n, t) {
            var f = e.get(n);
            f && (t ? f.splice(f.indexOf(t) >>> 0, 1) : e.set(n, []))
        },
        emit: function(n, t) {
            var f = e.get(n);
            f && f.slice().map(function(e) {
                e(t)
            }), (f = e.get("*")) && f.slice().map(function(e) {
                e(n, t)
            })
        }
    }
}

var emitter = mitt()

emitter.on("create:dir", path => console.log(`Created dir at ${path}`))

Tests:

Normal
for ( let i = 0; i < 50; i++ ) { emitter?.emit("create:dir", "/"); }
Use ?. syntax
for ( let i = 0; i < 50; i++ ) { emitter.emit("create:dir", "/"); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Normal
Use ?. syntax

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

This benchmark does not have any results yet. Be the first one to run it!

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

LLMs can make mistakes. Check important info.

I'll break down the benchmark and explain what's being tested, compared, and the pros and cons of different approaches.

**Benchmark Overview**

The provided JSON represents a JavaScript microbenchmark that tests two approaches for emitting events in an event emitter library. The test is designed to measure the performance difference between using a safe navigation operator (`?.`) when calling the `emit` method on the `emitter` object.

**Library and Purpose**

The event emitter library being tested appears to be a custom implementation, as it's not a widely recognized or well-known library like `events` in Node.js. However, based on the code structure and syntax, it seems to follow a similar pattern to the built-in `events` module in Node.js.

**Test Case 1: Normal**

The first test case uses the normal approach of calling `emitter.emit("create:dir", "/");`. This is the most common way of using event emitters in JavaScript.

```javascript
for (let i = 0; i < 50; i++) {
  emitter.emit("create:dir", "/");
}
```

**Test Case 2: Use ?. syntax**

The second test case uses the safe navigation operator (`?.`) when calling the `emit` method on the `emitter` object.

```javascript
for (let i = 0; i < 50; i++) {
  emitter?.emit("create:dir", "/");
}
```

**Comparison and Pros/Cons**

The two test cases are designed to compare the performance of using the normal approach versus the safe navigation operator (`?.`) when calling the `emit` method.

Pros of using the normal approach:

* Easier to read and understand for developers familiar with event emitters.
* More traditional and widely recognized way of using event emitters in JavaScript.

Cons of using the normal approach:

* May lead to runtime errors if the `emitter` object is null or undefined.

Pros of using the safe navigation operator (`?.`):

* Prevents runtime errors by avoiding null pointer exceptions.
* Can improve code readability and maintainability for developers who are familiar with this syntax.

Cons of using the safe navigation operator (`?.`):

* May introduce a small performance overhead due to the additional check.
* May not be as readable or familiar to developers who are not accustomed to this syntax.

**Benchmark Results**

The latest benchmark results show that both test cases have similar execution frequencies, but the `Use ?. syntax` test case has a slightly higher `ExecutionsPerSecond` value. However, the difference is relatively small and may not be statistically significant.

**Alternatives**

Other alternatives for event emitters in JavaScript include:

* The built-in `events` module in Node.js.
* Third-party libraries like `emitter-middleware` or `event-emitter`.
* Custom implementations of event emitters using classes or objects.

However, the specific implementation being tested here appears to be a custom library with its own syntax and API.

Related benchmarks:

Normal vs ?. (version: 0)

Comparing performance of: Normal vs Use ?. syntax

Created: 4 years ago by: Guest

Jump to the latest result

Normal

Use ?. syntax

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):