Benchmark: Switch vs Object Literal by surbina v3

Script Preparation code:

var str = 'abc';
str = str.charAt(Math.floor(Math.random() * 3));

function A() {
  console.log('A');
}

function B() {
  console.log('B');
}

function C() {
  console.log('C');
}

var objLiteral = {
  a: A,
  b: B,
  c: C
}

Tests:

Switch
var act; switch (str) { case 'a': act = A; break; case 'b': act = B; break; case 'c': act = C; break; } act();
Object Literal
objLiteral[str]();

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Switch
Object Literal

Fastest: N/A

Slowest: N/A

Latest run results:

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

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and explain what's being tested.

**Benchmark Definition**

The benchmark is defined by two different approaches:

1. **Switch Statement**: The first approach uses a traditional `switch` statement to determine which function to execute based on the value of the string variable `str`.
2. **Object Literal**: The second approach uses an object literal to store the functions and then accesses the desired function using the property name as a key.

**Options Compared**

The benchmark is comparing the performance of these two approaches:

* Traditional `switch` statement
* Object Literal

**Pros and Cons**

1. **Switch Statement**:
	* Pros: Can be more efficient for small numbers of cases, as it uses a jump table to resolve the case.
	* Cons: Can lead to slower execution times for larger numbers of cases due to the overhead of evaluating each case.
2. **Object Literal**:
	* Pros: More flexible and can handle dynamic properties or arbitrary data structures.
	* Cons: May be slower due to the overhead of creating and accessing objects.

In general, the switch statement is a good choice when the number of possible cases is small and predictable, while object literals are more suitable for scenarios where flexibility and dynamism are necessary.

**Library/Functionality**

Neither of these approaches requires any external libraries or special JavaScript features beyond basic syntax. However, it's worth noting that the `charCodeAt` function used in the script preparation code (`Math.floor(Math.random() * 3)` generates a random integer between 0 and 2) might be optimized by some browsers.

**Other Considerations**

* Cache locality: The switch statement can benefit from cache locality, where the CPU can store frequently accessed data in its cache. In contrast, object literals may have less cache locality due to their dynamic nature.
* Branch prediction: Some CPUs use branch prediction to predict the outcome of conditional statements like `switch`. This can affect performance.

**Alternatives**

Other alternatives to these approaches include:

1. **Function lookup tables (FLLs)**: Similar to switch statements, but using functions as keys instead of values. FLLs are often used in embedded systems and other low-level programming contexts.
2. **Polymorphic function calls**: Using techniques like function pointers or delegates to allow functions to be treated as values, rather than as standalone code blocks.

Overall, the choice of approach depends on the specific requirements of your use case, including factors like performance, flexibility, and maintainability.

Related benchmarks:

Switch vs Object Literal by surbina v3 (version: 0)

Comparing performance of: Switch vs Object Literal

Created: 6 years ago by: Guest

Jump to the latest result

Switch

Object Literal

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):