Benchmark: indexOf v.s. map

Script Preparation code:

var array = [];
for (var i=0; i<300; ++i) {
  	array.push('00' + i);
}

function hasWithIndexOf(needle) {
	return array.indexOf(needle) !== -1;
}

var map = {};
array.forEach(item => map[item] = true);

function hasWithMap(needle) {
	return needle in map;
}

Tests:

inexOf
for (var i=0; i<100; ++i) { hasWithIndexOf('404'); }
map
for (var i=0; i<100; ++i) { hasWithMap('404'); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
inexOf
map

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

This benchmark does not have any results yet. Be the first one to run it!

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 definition and test cases to understand what is being tested.

**Benchmark Definition**

The benchmark definition is a JSON object that describes two different approaches for finding an element in an array. The first approach uses the `indexOf()` method, while the second approach uses the `map` object.

```json
"Script Preparation Code": "var array = [];\r\nfor (var i=0; i<300; ++i) {\r\n  \tarray.push('00' + i);\r\n}\r\n\r\nfunction hasWithIndexOf(needle) {\r\n\treturn array.indexOf(needle) !== -1;\r\n}\r\n\r\nvar map = {};\r\narray.forEach(item => map[item] = true);\r\n\r\nfunction hasWithMap(needle) {\r\n\treturn needle in map;\r\n}",
```

This code creates an array of 300 elements, pushes them to the array, and then defines two functions: `hasWithIndexOf()` and `hasWithMap()`. The first function checks if a given element exists in the array using the `indexOf()` method. The second function uses the `map` object to create an associative array where each key is an element from the original array.

```json
"Html Preparation Code": null
```

This section is empty, which means that no HTML preparation code is required for this benchmark.

**Individual Test Cases**

There are two individual test cases:

```json
[
    {
        "Benchmark Definition": "for (var i=0; i<100; ++i) {\r\n\thasWithIndexOf('404');\r\n}",
        "Test Name": "inexOf"
    },
    {
        "Benchmark Definition": "for (var i=0; i<100; ++i) {\r\n\thasWithMap('404');\r\n}",
        "Test Name": "map"
    }
]
```

These test cases use the two functions defined in the benchmark definition and execute them 100 times each, checking for a specific element (`'404'`).

**Library**

The `Array.prototype.indexOf()` method is a built-in JavaScript method that returns the index of the first occurrence of an element in an array. It's used in the `hasWithIndexOf()` function.

There is no explicit library used in this benchmark definition, but it relies on built-in JavaScript methods and objects.

**Special JS Feature**

This benchmark doesn't use any special JavaScript features like async/await, Promises, or generators. However, it does use a technique called " closure" where the `hasWithMap()` function captures the scope of the original array by using the `forEach` method, which creates a new context for the function.

**Pros and Cons**

Here are some pros and cons of each approach:

1. **indexOf()**
	* Pros:
		+ Fast
		+ Widely supported
	* Cons:
		+ May not work well with large arrays or sparse arrays
		+ Returns -1 if the element is not found, which might be considered falsey in some contexts
2. **Map**
	* Pros:
		+ Can handle large arrays and sparse arrays
		+ Returns true as soon as the element is found
	* Cons:
		+ May have higher overhead due to object creation and iteration
		+ Not all browsers support `map` objects

**Other Alternatives**

Some other alternatives for finding an element in an array could be:

1. Using a binary search algorithm, which can be faster than the linear search used by `indexOf()`.
2. Using a data structure like a hash table or a trie, which can provide faster lookup times.
3. Using a library like Lodash or Ramda, which provides optimized and tested implementations of various array operations.

However, these alternatives might not be as widely supported or have the same simplicity as the built-in `indexOf()` method and the `map` object used in this benchmark definition.

Related benchmarks:

indexOf v.s. map (version: 0)

Comparing performance of: inexOf vs map

Created: 2 years ago by: Guest

Jump to the latest result

inexOf

map

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):