what is happening here? `def double_integer(i) i << 1 end` in ruby

The code you provided is a Ruby function called double_integer, which takes an integer i as its input. Inside the function, the << operator is used, which is a bitwise left shift operator in Ruby. It shifts the bits of the integer i to the left by 1 position.

In this specific code, the << operator is effectively multiplying the input integer i by 2. It is a shorthand way to double the value of the integer using bitwise operations.

Here's an example of how you can use this function:

main.rb
def double_integer(i)
  i << 1
end

num = 5
result = double_integer(num)
puts result
85 chars
8 lines

Output:

main.rb
10
3 chars
2 lines

In the above code, double_integer function is called with the input of num, which is 5. The function doubles the value using the bitwise left shift operation and returns the result. The final output is displayed as 10.