Unicode supported Regular expressions

unicode_regexp.rb

# /lib/unicode_regexp.rb
class UnicodeRegexp

# Returns string of Special Characters to be used in Regex
SPECIAL_CHARACTERS = [
  '\\~', '\\!', '\\@', '\\#', '\\$', '\\%', '\\^', '\\&', '\\*', '\\(', '\\)', '\\_', '\\+', '\\-',
  '\\=', '\\|', '\\{', '\\}', '\\[', '\\]', '\\:', '\\;', '\\"', '\\<', '\\>', '\\.', '\\?', '\\/',
  "\\\\\s" # Backslash & space character are purposely kept together in a string
].join

# Returns string of All the Digits of Unicode Character set
# Following list is taken from http://www.fileformat.info/info/unicode/category/Nd/list.htm
DIGITS = [
  (0x0030..0x0039).to_a,   # DIGIT ZERO to NINE
  (0x0660..0x0669).to_a,   # ARABIC-INDIC DIGIT ZERO to NINE
  (0x06F0..0x06F9).to_a,   # EXTENDED ARABIC-INDIC DIGIT ZERO to NINE
  (0x07C0..0x07C9).to_a,   # NKO DIGIT ZERO to NINE
  (0x0966..0x096F).to_a,   # DEVANAGARI DIGIT ZERO to NINE
  (0x09E6..0x09EF).to_a,   # BENGALI DIGIT ZERO to NINE
  (0x0A66..0x0A6F).to_a,   # GURMUKHI DIGIT ZERO to NINE
  (0x0AE6..0x0AEF).to_a,   # GUJARATI DIGIT ZERO to NINE
  (0x0B66..0x0B6F).to_a,   # ORIYA DIGIT ZERO to NINE
  (0x0BE6..0x0BEF).to_a,   # TAMIL DIGIT ZERO to NINE
  (0x0C66..0x0C6F).to_a,   # TELUGU DIGIT ZERO to NINE
  (0x0CE6..0x0CEF).to_a,   # KANNADA DIGIT ZERO to NINE
  (0x0D66..0x0D6F).to_a,   # MALAYALAM DIGIT ZERO to NINE
  (0x0E50..0x0E59).to_a,   # THAI DIGIT ZERO to NINE
  (0x0ED0..0x0ED9).to_a,   # LAO DIGIT ZERO to NINE
  (0x0F20..0x0F29).to_a,   # TIBETAN DIGIT ZERO to NINE
  (0x1090..0x1099).to_a,   # MYANMAR SHAN DIGIT ZERO to NINE
  (0x17E0..0x17E9).to_a,   # KHMER DIGIT ZERO to NINE
  (0x1810..0x1819).to_a,   # MONGOLIAN DIGIT ZERO to NINE
  (0x1946..0x194F).to_a,   # LIMBU DIGIT ZERO to NINE
  (0x19D0..0x19D9).to_a,   # NEW TAI LUE DIGIT ZERO to NINE
  (0x1A80..0x1A99).to_a,   # TAI THAM HORA DIGIT ZERO to NINE
  (0x1B50..0x1B59).to_a,   # BALINESE DIGIT ZERO to NINE
  (0x1BB0..0x1BB9).to_a,   # SUNDANESE DIGIT ZERO to NINE
  (0x1C40..0x1C49).to_a,   # LEPCHA DIGIT ZERO to NINE
  (0x1C50..0x1C59).to_a,   # OL CHIKI DIGIT ZERO to NINE
  (0xA620..0xA629).to_a,   # VAI DIGIT ZERO to NINE
  (0xA8D0..0xA8D9).to_a,   # SAURASHTRA DIGIT ZERO to NINE
  (0xA900..0xA909).to_a,   # KAYAH LI DIGIT ZERO to NINE
  (0xA9D0..0xA9D9).to_a,   # JAVANESE DIGIT ZERO to NINE
  (0xAA50..0xAA59).to_a,   # CHAM DIGIT ZERO to NINE
  (0xABF0..0xABF9).to_a,   # MEETEI MAYEK DIGIT ZERO to NINE
  (0xFF10..0xFF19).to_a,   # FULLWIDTH DIGIT ZERO to NINE
  (0x104A0..0x104A9).to_a, # OSMANYA DIGIT ZERO to NINE
  (0x11066..0x1106F).to_a, # BRAHMI DIGIT ZERO to NINE
  (0x110F0..0x110F9).to_a, # SORA SOMPENG DIGIT ZERO to NINE
  (0x11136..0x1113F).to_a, # CHAKMA DIGIT ZERO to NINE
  (0x111D0..0x111D9).to_a, # SHARADA DIGIT ZERO to NINE
  (0x116C0..0x116C9).to_a, # TAKRI DIGIT ZERO to NINE
  (0x1D7CE..0x1D7D7).to_a, # MATHEMATICAL BOLD DIGIT ZERO to NINE
  (0x1D7D8..0x1D7E1).to_a, # MATHEMATICAL DOUBLE-STRUCK DIGIT ZERO to NINE
  (0x1D7E2..0x1D7EB).to_a, # MATHEMATICAL SANS-SERIF DIGIT ZERO to NINE
  (0x1D7EC..0x1D7F5).to_a, # MATHEMATICAL SANS-SERIF BOLD DIGIT ZERO to NINE
  (0x1D7F6..0x1D7FF).to_a  # MATHEMATICAL MONOSPACE DIGIT ZERO to NINE
].flatten.map(&:chr).join

  class << self

    regexps = {
      # Excludes all special characters & digits
      only_characters: Regexp.new(/^([^#{SPECIAL_CHARACTERS}#{DIGITS}]+\s{0,1})+$/),
      # Includes only Digits
      only_digits: Regexp.new(/^[#{DIGITS}]+$/),
      # Excludes all special characters
      characters_and_numbers: Regexp.new(/^([^#{SPECIAL_CHARACTERS}]+\s{0,1})+$/),
      # Only special characters' string not allowed rest all combinations allowed
      exclude_only_special_characters: Regexp.new(/^([^#{SPECIAL_CHARACTERS}]+(.)*)+$/),
    }

    regexps.each_pair do |attribute, regex|

      define_method attribute do
        regex
      end

    end

  end

end

user.rb

# /app/models/user.rb
class User < ActiveRecord::Base

  validates :mobile,
            format: { with: UnicodeRegexp.only_digits }

end