VerEx.rb

# This is a program trying to implement Verbal Expressions
# See this for more info - http://verbalexpressions.github.io/

def VerEx
  VerExClass.new
end

class VerExClass
  attr_accessor :regex
  
  def intitialize(regex = "")
    self.regex = regex
  end
  
  def final_regexp
    Regexp.new(regex)
  end
  
  def add(value)
    regex << value
    
    self
  end
  alias_method :<<, :add
  
  def start_of_line
    add("^")
  end
  
  def end_of_line
    add("$")
  end
  
  def find(value)
    add("(" + Regexp.escape(value) + ")")
  end
  
  def then(value)
    find(Regexp.escape(value))
  end
  
  def maybe(value)
    add("(" + Regexp.escape(value) + ")?")
  end
  
  def anything
    add("(?:.*)")
  end
  
  def anything_but(value)
    add("([^" + Regexp.escape(value) + "]*)")
  end
  
  def something 
    add("(?:.+)")
  end
  
  def something_but(value)
    add("(?:[^" + Regexp.escape(value) + "]+)")
  end
  
  def line_break
    add("(?:(?:\n)|(?:\r\n))")
  end
  
  def tab
    add("\t")
  end
  
  def match(string)
    final_regexp.match(string)
  end
end

# Tests - 

if __FILE__ == $0 
  verex = VerEx.
    start_of_line.
    find('http').
    maybe('s').
    find('://').
    maybe('www.').
    anything_but(' ').
    end_of_line
  
  if verex.match("https://www.google.com")
    puts "Matched"
  else
    puts "Not matched"
  end
  
  puts verex.final_regexp
  puts "^(http)(s)?(\:\/\/)(www\.)?([^\ ]*)$"
  
  if verex.final_regexp.match("https://google.com")
    puts "True"  
  end
end