Benchmark: object map vs switch

Script Preparation code:

var arr = [1, 2, 3, 4, 5]

Tests:

object map
const val = arr.at(Math.floor(Math.random() * 5)) const obj = { [1]: 'a', [2]: 'b', [3]: 'c', [4]: 'd', [5]: 'e' } const rt = obj[val]
switch
const val = arr.at(Math.floor(Math.random() * 5)) switch (val) { case 1: return 'a'; case 2: return 'b'; case 3: return 'c'; case 4: return 'd'; case 5: return 'e'; default: return ''; }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
object map
switch

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/17.2 Safari/605.1.15

Browser/OS: Safari 17 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
object map	5344812.5 Ops/sec
switch	7382304.0 Ops/sec

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

LLMs can make mistakes. Check important info.

**Overview**

The provided benchmark tests two approaches for accessing elements in an object: `object map` and `switch`. The test creates an array of numbers from 1 to 5, generates a random number between 1 and 5 using `Math.random()`, and then uses this value as the key to access the corresponding string value in the object.

**Benchmark Definition**

The benchmark definition provides two scripts for each test case:

*   "object map": This script uses the bracket notation (`obj[val]`) to access the element in the object.
*   "switch": This script uses a `switch` statement with cases for each possible value of `val`.

**Options Compared**

The benchmark compares the performance of two approaches:

1.  **Object Bracket Notation (object map)**: This approach uses the bracket notation (`obj[val]`) to access the element in the object.
2.  **Switch Statement**: This approach uses a `switch` statement with cases for each possible value of `val`.

**Pros and Cons**

*   **Object Bracket Notation (object map)**:
    *   Pros: concise, easy to read, and works well for arrays where keys are sequential.
    *   Cons: may be slower due to the overhead of object lookups.
*   **Switch Statement**:
    *   Pros: can be faster for large numbers of cases, as it eliminates the need for object lookups.
    *   Cons: more verbose and harder to read than bracket notation.

**Library Used**

There is no specific library used in this benchmark. However, JavaScript does provide some built-in objects like `Math` which contains functions that can be utilized to get the random number.

**Special JS Feature or Syntax**

There are none mentioned specifically in the provided benchmark code.

**Other Alternatives**

If you need to access elements in an object, other alternatives might include:

*   **Using a `for...in` loop**: This approach involves using a loop to iterate over the keys of the object and then accessing the corresponding value.
*   **Using the `in` operator**: Similar to bracket notation, but uses the `in` operator to check if a key exists in the object.

**Performance Considerations**

When choosing between these approaches, consider the following factors:

*   **Array size**: For small arrays, bracket notation might be faster. However, for large arrays, switch statements can provide better performance.
*   **Object structure**: If your objects have sequential keys (like an array), bracket notation is usually a good choice. However, if your objects are sparse or have many duplicate keys, switch statements may be more efficient.

**Benchmark Best Practices**

When running benchmarks like this one:

*   Run multiple iterations to get accurate results.
*   Use a consistent environment and testing setup.
*   Consider using a profiling tool to identify performance bottlenecks in your code.

Related benchmarks:

object map vs switch (version: 0)

Comparing performance of: object map vs switch

Created: 2 years ago by: Guest

Jump to the latest result

object map

switch

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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