class Chronic::Parser

def pre_normalize(text)

Returns a new String ready for Chronic to parse.

#=> "136 days future this second"
Chronic.pre_normalize('one hundred and thirty six days from now')

#=> "next day future 12:00"
Chronic.pre_normalize('tomorrow after noon')

#=> "1st day in may"
Chronic.pre_normalize('first day in May')

Examples:

text - The String text to normalize.

ordinals (third => 3rd)
(three => 3), and converting ordinal words to numeric
idioms to their canonical form, converting number words to numbers
Clean up the string by stripping unwanted characters, converting

Clean up the specified text ready for parsing. 
def pre_normalize(text)
  text = text.to_s.downcase
  text.gsub!(/\b(\d{2})\.(\d{2})\.(\d{4})\b/, '\3 / \2 / \1')
  text.gsub!(/\b([ap])\.m\.?/, '\1m')
  text.gsub!(/(\s+|:\d{2}|:\d{2}\.\d{3})\-(\d{2}:?\d{2})\b/, '\1tzminus\2')
  text.gsub!(/\./, ':')
  text.gsub!(/([ap]):m:?/, '\1m')
  text.gsub!(/['"]/, '')
  text.gsub!(/,/, ' ')
  text.gsub!(/^second /, '2nd ')
  text.gsub!(/\bsecond (of|day|month|hour|minute|second)\b/, '2nd \1')
  text = Numerizer.numerize(text)
  text.gsub!(/([\/\-\,\@])/) { ' ' + $1 + ' ' }
  text.gsub!(/(?:^|\s)0(\d+:\d+\s*pm?\b)/, ' \1')
  text.gsub!(/\btoday\b/, 'this day')
  text.gsub!(/\btomm?orr?ow\b/, 'next day')
  text.gsub!(/\byesterday\b/, 'last day')
  text.gsub!(/\bnoon\b/, '12:00pm')
  text.gsub!(/\bmidnight\b/, '24:00')
  text.gsub!(/\bnow\b/, 'this second')
  text.gsub!('quarter', '15')
  text.gsub!('half', '30')
  text.gsub!(/(\d{1,2}) (to|till|prior to|before)\b/, '\1 minutes past')
  text.gsub!(/(\d{1,2}) (after|past)\b/, '\1 minutes future')
  text.gsub!(/\b(?:ago|before(?: now)?)\b/, 'past')
  text.gsub!(/\bthis (?:last|past)\b/, 'last')
  text.gsub!(/\b(?:in|during) the (morning)\b/, '\1')
  text.gsub!(/\b(?:in the|during the|at) (afternoon|evening|night)\b/, '\1')
  text.gsub!(/\btonight\b/, 'this night')
  text.gsub!(/\b\d+:?\d*[ap]\b/,'\0m')
  text.gsub!(/\b(\d{2})(\d{2})(am|pm)\b/, '\1:\2\3')
  text.gsub!(/(\d)([ap]m|oclock)\b/, '\1 \2')
  text.gsub!(/\b(hence|after|from)\b/, 'future')
  text.gsub!(/^\s?an? /i, '1 ')
  text.gsub!(/\b(\d{4}):(\d{2}):(\d{2})\b/, '\1 / \2 / \3') # DTOriginal
  text.gsub!(/\b0(\d+):(\d{2}):(\d{2}) ([ap]m)\b/, '\1:\2:\3 \4')
  text
end