explain `[3, 1, 4, 1, 5, 9, 2, 6, 5, 3, 5].chunk { |n| n.even? }.each { |even, ary| p [even, ary] }` in ruby

The code you provided is using the chunk method in Ruby to group consecutive elements in an array based on a condition. Here's how it works:

1. [3, 1, 4, 1, 5, 9, 2, 6, 5, 3, 5] is the input array that we want to chunk.
2. .chunk { |n| n.even? } is called on the array. It takes a block of code as an argument and evaluates it for each element in the array.
3. The block of code n.even? checks if each number n in the array is even or not. If it is even, the chunk method considers it as a key to group elements. If it is odd, the chunk method creates a new group.
4. The chunk method returns an enumerator that yields both the key and an array of grouped elements.
5. .each { |even, ary| p [even, ary] } is then called on the enumerator returned by the chunk method. It iterates over each chunk and prints the key (even) and the array of grouped elements (ary).

The output of the code will be:

main.rb
[false, [3, 1]]
[true, [4]]
[false, [1, 5, 9]]
[true, [2, 6]]
[false, [5, 3, 5]]
81 chars
6 lines

In the output, each line represents a chunk where the first element is the condition (even), and the second element is the array (ary) containing the grouped elements based on the condition.

So, the code is chunking the array [3, 1, 4, 1, 5, 9, 2, 6, 5, 3, 5] into groups of consecutive even and odd numbers.

Please note that the code you provided is missing parentheses around the array, and it should be as follows:

main.rb
[3, 1, 4, 1, 5, 9, 2, 6, 5, 3, 5].chunk { |n| n.even? }.each { |even, ary| p [even, ary] }
91 chars
2 lines

I hope this explanation helps! Let me know if you have any further questions.