Benchmark: if-else vs switch test

Tests:

Switch case
const a = 1; switch (a) { case 5: console.log("a is 5"); break; case 4: console.log("a is 4"); break; case 3: console.log("a is 4"); break; case 444: console.log("a is 4"); break; case 355: console.log("a is 4"); break; case 2: console.log("a is 2"); break; case 1: console.log("a is 1"); break; }
if-else
const a = 1; if (a == 5) { console.log("a is 5"); } else if (a == 4) { console.log("a is 4"); } else if (a == 5) { console.log("a is 4"); } else if (a == 6) { console.log("a is 4"); } else if (a == 3) { console.log("a is 4"); } else if (a == 2) { console.log("a is 2"); } else if (a == 1) { console.log("a is 1"); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Switch case
if-else

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/115.0.0.0 Safari/537.36

Browser/OS: Chrome 115 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Switch case	313300.6 Ops/sec
if-else	307729.5 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into explaining the benchmark.

**Benchmark Definition**

The provided JSON represents a JavaScript microbenchmark that tests two different approaches to handle multiple cases: `switch` statements and `if-else` statements.

**Switch Statement vs If-Else**

In this benchmark, both approaches are used to print messages based on the value of variable `a`. The values of `a` are 1, 2, 3, 4, 5, and 444 (not 6 as it's used in one of the if-else cases).

**Options Compared**

The benchmark compares two approaches:

1. **Switch Statement**: This approach uses a `switch` statement to handle multiple cases. The `case` labels are specified, and the corresponding code is executed based on the value of `a`.
2. **If-Else**: This approach uses nested `if-else` statements to handle multiple cases.

**Pros and Cons**

*   **Switch Statement**:
    *   Pros:
        *   More concise and readable.
        *   Easier to maintain and modify, as it reduces nesting.
        *   Can be faster in some cases (depending on the JavaScript engine's implementation).
    *   Cons:
        *   Only supported by browsers that support `switch` statements with multiple labels (most modern browsers do).
*   **If-Else**:
    *   Pros:
        *   Widely supported across different browsers and platforms.
        *   Can be used for more complex logic and conditional statements.
    *   Cons:
        *   More verbose and harder to read, especially with deep nesting.
        *   Can lead to performance issues due to excessive execution.

**Special Consideration: If Statement Repetition**

In the `if-else` test case, there's a notable repetition of an `if` statement (i.e., `if (a == 5)` followed by `else if (a == 5)`) which is unnecessary and redundant. This might lead to performance implications.

**Library Usage**

There are no libraries mentioned in the benchmark definition or individual test cases.

**Special Feature/ Syntax**

None mentioned.

**Alternatives**

If you're looking for alternative approaches, consider:

1.  **Use `Object` with `hasOwnProperty()`**: Instead of using a switch statement or if-else, you can use an object and check if a specific property exists.
    ```javascript
const obj = {
    value: function() {
        const val = this.a;
        if (val in this) {
            return 'a is ' + val;
        } else {
            return "Error";
        }
    },
};
```
2.  **Use `enum`**: Some modern browsers support the `enum` keyword, which can be used for switch statements.
    ```javascript
const a = 1;

console.log(
    switch (a) {
        case 5:
            console.log("a is 5");
            break;
        case 4:
            console.log("a is 4");
            break;
        // ... and so on
```

3.  **Use `Pattern Matching`**: Some JavaScript engines support pattern matching, which can be used for switch-like functionality.
    ```javascript
const a = 1;

console.log(
    a === 5 ? console.log("a is 5") : "Error"
);

```
Keep in mind that these alternatives might not provide exactly the same behavior as `switch` or `if-else`, but they can offer different approaches to handle multiple cases.

In summary, the benchmark provides an opportunity to compare two widely used approaches: `switch` statements and `if-else`. The results help developers understand the performance implications of each approach in JavaScript.

Related benchmarks:

if-else vs switch test (version: 0)

Comparing performance of: Switch case vs if-else

Created: one year ago by: Guest

Jump to the latest result

Switch case

if-else

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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