Benchmark: if-else vs switch vs object

Script Preparation code:

class Host {
    A = 1;
    B = 2;
    C = 3;
}

var host = new Host();

var x = Math.floor(Math.random() * 3);

function testObject(h, p) {
    const obj = {
        [h.A]: 1,
        [h.B]: 2,
        [h.C]: 3,
    }

    return obj[p];
}


function testIfElse(h, p) {
    var v = 0;
    if (p === h.A) {
        v = 1;
    } else if (p === h.B) {
        v = 2;
    } else if (p === h.C) {
        v = 3;
    }
    return v;
}

function testSwitch(h, p) {
    let v = 0;
    switch (p) {
        case h.A:
            v = 1;
            break;
        case h.B:
            v = 2;
            break;
        case h.B:
            v = 3;
            break;
    }
    return v;
}

Tests:

object
testObject(host, x);
if-else
testIfElse(host, x);
switch
testSwitch(host, x)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
object
if-else
switch

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

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

LLMs can make mistakes. Check important info.

The provided JSON represents the benchmark definition and test cases for measuring JavaScript performance.

**Benchmark Definition**

The benchmark is designed to compare three different approaches:

1.  **Object access**: This approach uses an object with dynamic property access, where the property name is determined by the `x` variable.
2.  **If-else statement**: This approach uses a traditional if-else statement to determine the value of the variable.
3.  **Switch statement**: This approach uses a switch statement to determine the value of the variable.

The script preparation code includes classes and functions that define the behavior for each approach, as well as variables and constants used in the benchmarking process.

**Options Compared**

The benchmark compares the performance of three options:

*   Object access ( `testObject` function)
*   If-else statement ( `testIfElse` function)
*   Switch statement ( `testSwitch` function)

These approaches are compared on a microbenchmark scale, which means they focus on measuring small code snippets and execution times.

**Pros and Cons**

Here's a brief overview of the pros and cons of each approach:

*   **Object Access**: This approach is generally faster than traditional if-else statements because it uses a more efficient way to access properties. However, it can be slower for certain cases where the property name is not known at compile-time.
*   **If-Else Statement**: Traditional if-else statements are widely supported and easy to read. They are suitable for most use cases but might be slower than object-based approaches.
*   **Switch Statement**: Switch statements are suitable for specific cases, especially when the number of cases is limited. However, they can be slower due to the overhead of case resolution.

**Library Usage**

The `Host` class in the script preparation code is used as a context object for the three test functions (object access, if-else statement, and switch statement). The purpose of this library is to provide a fixed value (`A=1`, `B=2`, and `C=3`) that can be dynamically accessed using property names.

**Special JS Features or Syntax**

The benchmark does not specifically utilize any special JavaScript features or syntax. It only uses standard JavaScript constructs, such as classes, functions, variables, and conditional statements.

**Alternatives**

Other alternatives for comparing these approaches include:

*   Profiling tools: These can provide detailed performance metrics without requiring explicit benchmarking.
*   Just-In-Time (JIT) compilers: Some engines like V8 have JIT compilers that analyze code at runtime to optimize performance.
*   Native code implementations: Compilers like GCC or Clang can be used to generate optimized native machine code for specific use cases.

These alternatives provide additional perspectives on optimizing performance, but the benchmark's focus is on comparing different JavaScript approaches using a controlled environment.

Related benchmarks:

if-else vs switch vs object (version: 0)

Comparing performance of: object vs if-else vs switch

Created: 3 years ago by: Guest

Jump to the latest result

object

if-else

switch

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):