Benchmark: Array Exists vs If...else

HTML Preparation code:

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Tests:

If..else
const cidadeFilial = 'GUARUJA'; if(cidadeFilial == 'SAO PAULO'){return 'Filial01';} else if(cidadeFilial == 'RIO DE JANEIRO'){return 'Filial02';} else if(cidadeFilial == 'CURITIBA'){return 'Filial03';} else if(cidadeFilial == 'FLORIANOPOLIS'){return 'Filial03';} else if(cidadeFilial == 'SANTOS'){return 'Filial04';} else if(cidadeFilial == 'GUARUJA'){return 'Filial05';} else if(cidadeFilial == 'BELO HORIZONTE'){return 'Filial05';} else {return 'Central';}
Array
const cidadeFilial = 'GUARUJA'; const filiais = { 'SAO PAULO': 'Filial01', 'RIO DE JANEIRO': 'Filial02', 'CURITIBA': 'Filial03', 'FLORIANOPOLIS': 'Filial03', 'SANTOS': 'Filial04', 'GUARUJA': 'Filial05', 'BELO HORIZONTE': 'Filial05' } return filiais[cidadeFilial] ?? 'Central'

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
If..else
Array

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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Let's dive into the explanation of the provided benchmark.

**What is being tested?**

The benchmark measures the performance difference between two approaches:

1. **If-else statement**: A classic conditional statement that checks if a condition is true and executes a corresponding block of code if it is.
2. **Array lookup**: A method that uses an array to store values and looks up a specific value in the array.

**Options compared**

The benchmark compares the performance of two options:

1. **If-else statement**: This option checks for exact matches between the `cidadeFilial` variable and the keys in the `filiais` object.
2. **Array lookup**: This option uses the `??` operator to look up the value associated with `cidadeFilial` in the `filiais` object.

**Pros and cons of each approach**

1. **If-else statement**
	* Pros:
		+ Easy to understand and maintain
		+ Can handle non-existent values (returns 'Central' in this case)
	* Cons:
		+ May be slower due to the overhead of checking multiple conditions
		+ Requires explicit key-matching
2. **Array lookup**
	* Pros:
		+ Efficient for large datasets, as it uses a single operation to look up values
		+ Allows for easy addition or removal of keys without modifying the code
	* Cons:
		+ May be slower due to the overhead of looking up values in an array
		+ Requires understanding of the `??` operator and its behavior

**Library and special JS feature**

In this benchmark, the `??` operator is used. This is a modern JavaScript feature called the "Nullish Coalescing Operator" (?:), which was introduced in ECMAScript 2020. It allows you to provide a default value when looking up a key in an object that may not exist.

**Other considerations**

* The benchmark uses a simple, test-driven approach to measure performance differences between the two options.
* The `filiais` object is defined statically, which means its contents are known at compile-time. This can impact performance compared to dynamically loaded data.
* The use of `const` and `let` declarations ensures that variables are not reassigned or modified unexpectedly.

**Alternatives**

Other approaches to achieve the same result could include:

1. Using a `switch` statement instead of an if-else chain
2. Utilizing a library like Lodash's `get` function for array lookups
3. Implementing a custom lookup mechanism using a data structure like a hash table or trie

However, these alternatives may not provide the same performance benefits as the array lookup approach, and may require additional complexity and overhead.

Related benchmarks:

Array Exists vs If...else (version: 0)

Comparing performance of: If..else vs Array

Created: 6 years ago by: Guest

Jump to the latest result

If..else

Array

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):