Benchmark: JS switch vs if/else if

Script Preparation code:

var test = 'test'

Tests:

switch
switch(test) { case 'test1': return true; case 'test2': return true; case 'test3': return true; case 'test4': return true; case 'test5': return true; default: return true; }
if/else if
if (test === 'test1') { return true; } else if (test === 'test2') { return true; } else if (test === 'test3') { return true; } else if (test === 'test4') { return true; } else if (test === 'test5') { return true; }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
switch
if/else if

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 8 days ago)

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/115.0

Browser/OS: Firefox 115 on Linux

View result in a separate tab

Test name	Executions per second
switch	116817392.0 Ops/sec
if/else if	117654768.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the benchmark and explain what's being tested, compared, and the pros and cons of each approach.

**Benchmark Definition**

The benchmark is designed to compare the speed difference between using multiple `IF` statements (with nested `else if`) and an open-ended `switch` statement. The test case uses a variable `test` with predefined values `'test1'`, `'test2'`, `'test3'`, `'test4'`, and `'test5'`.

**Script Preparation Code**

The script preparation code is simple: `var test = 'test'`. This sets the value of the `test` variable, which will be used in both benchmark definitions.

**Html Preparation Code**

There is no HTML preparation code provided, so we'll assume it's not relevant for this specific benchmark.

**Individual Test Cases**

We have two test cases:

1. **switch**: This test case uses a `switch` statement with multiple `case` statements to check the value of the `test` variable.
2. **if/else if**: This test case uses nested `IF` statements (with `else if`) to check the value of the `test` variable.

**Library Usage**

There is no explicit library usage mentioned in the benchmark definition or script preparation code. However, it's possible that some libraries might be required for the benchmark results to make sense (e.g., for measuring execution time).

**Special JS Features/Syntax**

The benchmark uses the following special JavaScript features/syntax:

* **Switch statement**: The `switch` statement is used in one of the test cases.
* **Nested IF statements**: The `if/else if` test case uses nested `IF` statements, which can lead to slower execution times due to increased branching.

**Pros and Cons**

Here are some pros and cons of each approach:

* **Switch Statement (switch)**:
	+ Pros: Can be faster for certain types of data (e.g., strings) since it allows the compiler to optimize directly. Also, less code is required.
	+ Cons: May not work well with non-numeric or non-string data types. Also, can lead to slower execution times if the number of cases exceeds 10.
* **Nested IF Statements (if/else if)**:
	+ Pros: Can be more flexible for certain use cases since it allows for multiple conditions and nested logic.
	+ Cons: Can lead to slower execution times due to increased branching. Also, requires more code.

**Other Considerations**

When choosing between these approaches, consider the following:

* **Type of data**: If you're working with strings or numeric data, `switch` might be a better choice. For non-numeric or non-string data types, `if/else if` might be necessary.
* **Number of cases**: If you have a large number of cases in your switch statement, it might be more efficient to use an array-based lookup instead (not shown in this benchmark).
* **Code readability**: Both approaches can lead to readable code, but nested `IF` statements can make the code harder to understand.

**Other Alternatives**

If you're looking for alternative approaches, consider:

* **Arrays and binary search**: Instead of using a switch statement or if/else chain, you could use an array-based lookup with binary search. This approach would be faster for large numbers of cases.
* **Object-based lookups**: If your data is structured as objects, you could use object-based lookups instead of switch statements or if/else chains.

Keep in mind that these alternatives might require more complex code and may not always lead to performance gains.

Related benchmarks:

JS switch vs if/else if (version: 0)

Benchmark of the speed difference between using multiple IF statements and an open-ended IF/ELSE IF.

Comparing performance of: switch vs if/else if

Created: 3 years ago by: Guest

Jump to the latest result

switch

if/else if

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):