Benchmark: Reduce vs map/join

Script Preparation code:

var strings = [];
for (var i=0; i<1000; i++) {
  strings[i] = ""+i+i;
}

Tests:

for
var result = ""; for (var i=0; i<strings.length; i++) { result = result+' x-'+strings[i]; }
reduce
var result = strings.reduce(function(string, i) { return string+' x-'+i; }, "");
map
var result = strings.map(function(string, i) { return "x-"+i; }).join(' ');

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
for
reduce
map

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 10 months ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:140.0) Gecko/20100101 Firefox/140.0

Browser/OS: Firefox 140 on Windows

View result in a separate tab

Test name	Executions per second
for	178214.0 Ops/sec
reduce	122580.7 Ops/sec
map	43262.3 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the provided JSON benchmark and explain what's being tested.

**Benchmark Definition**
The benchmark is comparing three approaches to concatenate strings:

1. **For loop**: A traditional for loop that iterates over an array of strings, concatenating each string with `x-` prefix using string multiplication (`+` operator).
2. **Array.prototype.reduce()**: The reduce method reduces an array of strings into a single string by applying a callback function to each element in the array.
3. **Array.prototype.map() + Array.prototype.join()**: A two-step approach where map is used to transform an array of strings into an array of strings with `x-` prefix, and then join is used to concatenate these strings.

**Options Compared**

* For loop:
	+ Pros: Easy to understand, flexible, and can be used in many contexts.
	+ Cons: May have performance issues due to string concatenation in a loop.
* Array.prototype.reduce():
	+ Pros: More concise, efficient, and often preferred for data transformations.
	+ Cons: Can be less intuitive for those not familiar with the reduce method.
* Array.prototype.map() + Array.prototype.join():
	+ Pros: Efficient, scalable, and suitable for large datasets.
	+ Cons: Requires two methods (map and join), which can lead to more overhead.

**Library**
The benchmark uses `strings` as an array of strings. There is no specific library mentioned in the JSON data.

**Special JS Features/Syntax**
None are explicitly used in this benchmark, but keep in mind that some libraries or implementations might use advanced JavaScript features like async/await, Promises, or modern language features for performance optimizations.

**Other Considerations**

* The benchmark runs on Safari 11 on a Mac with Intel Mac OS X 10.13.4.
* Each test case executes at different frequencies (43523.25, 3233.9296875, and 2668.519287109375 executions per second).
* The results are likely to be influenced by the specific browser and platform used.

**Alternative Approaches**
Other approaches could include:

* Using a string buffer or StringBuilder class to concatenate strings in a loop.
* Leveraging `join()` with an empty string (`''`) as the separator for each element in the array.
* Utilizing a library like Lodash, which provides a `reduceRight()` method for array reductions.

These alternatives might offer varying trade-offs between readability, performance, and conciseness.

Related benchmarks:

Reduce vs map/join (version: 0)

Comparing performance of: for vs reduce vs map

Created: 7 years ago by: Guest

Jump to the latest result

for

reduce

map

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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