Split a String at a "line-break" character in Ruby

split.rb

# Task:
# implement different ways to split a string at a line-break character into lines
# for the sake of simplicity these examples use "0" as "line-break" character


# this solves only a part of the task recursivly 
def detect_first_line(string, line = "", position = 0)
  return line if string[position] == "0"

  puts "#{position}, #{string[position]}, #{line}"
  
  detect_first_line(string, line + string[position], position + 1)  

  # puts "#{position}, #{string[position]}, #{line}" # comment this in and inspect the output
end
# => detect_first_line("germany0spain0sweden")


def split_recursive(string, position = 0, lines = [], line_number = 0)
  # when it finds a line-break character, it skips it and increments the line_number
  return split_recursive(string, position + 1, lines, line_number + 1) if string[position] == "0" # remove the "return", run the code and inspect the output
  
  lines[line_number] = lines[line_number].to_s + string[position] # for each new line the array is empty and nil.to_s => ""

  puts "#{position}, #{string[position]}, #{lines}"

  return lines if position == string.length - 1
  
  split_recursive(string, position + 1, lines, line_number)  
end
# => split_recursive("germany0spain0sweden")


def split_for_loop(string)
  lines = []
  line_number = 0
  
  for position in 0..(string.length - 1) do
    if string[position] == "0"
      line_number += 1
      next
    end
    lines[line_number] = lines[line_number].to_s + string[position]

    puts "#{position}, #{string[position]}, #{lines}"
  end

  lines
end
# => split_for_loop("germany0spain0sweden")


def split_enumerator(string)
  lines = []
  line_number = 0
  
  string.each_char do |c|
    if c == "0"
      line_number += 1
      next
    end

    lines[line_number] = lines[line_number].to_s + c

    puts "#{c}, #{lines}"
  end

  lines
end
# => split_enumerator("germany0spain0sweden")


# idiomatic Ruby
"germany0spain0sweden".split("0")