Benchmark: Map vs Object with check

Script Preparation code:

var map = new Map();
var obj = {};

map.set('a', 5);
obj['a'] = 5;

var i = 0, count = 1000, a;

Tests:

Map lookup
for (i = 0; i < count; i++) { if(map.has(i)){ a = map.get('a'); } }
Obj lookup
for (i = 0; i < count; i++) { if(obj['a']){ a = obj['a']; } }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Map lookup
Obj lookup

Fastest: N/A

Slowest: N/A

Latest run results:

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

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I'd be happy to help you understand the provided JavaScript benchmark.

**Benchmark Overview**

The test case compares the performance of two data structures: `Map` and `Object`. A `Map` is a built-in JavaScript object that stores key-value pairs, while an `Object` is a more traditional way of storing data in JavaScript. The goal is to measure which approach is faster for a simple lookup operation.

**Benchmark Preparation Code**

The script preparation code creates two objects: `map` and `obj`. It then sets the value `'a'` to 5 using the `Map.set()` method and the `Object['a'] = 5` syntax. Finally, it initializes variables `i`, `count`, and `a`.

**Html Preparation Code**

The HTML preparation code is empty in this case.

**Individual Test Cases**

There are two test cases:

1. **Map Lookup**: This test case uses a loop to iterate `count` times (1000). Inside the loop, it checks if the current iteration number `i` exists as a key in the `map`. If it does, it retrieves the value associated with key `'a'` using the `map.get()` method. The variable `a` is assigned the retrieved value.
2. **Object Lookup**: This test case uses a similar loop structure to the map lookup test case. However, instead of using the `Map.has()` and `map.get()` methods, it checks if the property `'a'` exists in the `obj` object using the bracket notation (`obj['a']`). If it does, it assigns the value associated with key `'a'` to the variable `a`.

**Library Usage**

In both test cases, no external libraries are used.

**Special JavaScript Feature/Syntax**

The test case uses a few special JavaScript features:

* **Template literals**: The script preparation code uses template literals to create a string that contains multiple lines. Template literals allow you to embed expressions inside string literals.
* **Arrow functions**: The loop counters `i` and the increment operator `++` use arrow functions, which are shorthand for function declarations.

**Pros and Cons of Approaches**

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

1. **Map Lookup**:
	* Pros: Maps are optimized for fast lookups, and the `map.get()` method is likely to be faster than checking an object's properties using bracket notation.
	* Cons: The `Map` data structure has a higher overhead compared to traditional objects due to its internal implementation.
2. **Object Lookup**:
	* Pros: Bracket notation is often more readable and efficient for simple property lookups.
	* Cons: Checking if a property exists before looking it up can be slower than using the `has()` method on a map.

**Other Alternatives**

If you want to explore alternative approaches, here are some options:

1. **Use a different data structure**: Instead of using a `Map` or an `Object`, consider using other data structures like arrays or sets.
2. **Use caching mechanisms**: Implementing caching mechanisms can improve performance for frequent lookups.
3. **Simplify the test case**: You could simplify the test cases by removing unnecessary operations or reducing the number of iterations.

Keep in mind that the best approach will depend on your specific use case and requirements. The Map vs Object comparison is a common benchmark to evaluate JavaScript engine performance, but it may not be representative of real-world scenarios where more complex data structures and caching mechanisms are used.

Related benchmarks:

Map vs Object with check (version: 0)

Lookup of map vs object

Comparing performance of: Map lookup vs Obj lookup

Created: 4 years ago by: Guest

Jump to the latest result

Map lookup

Obj lookup

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):