Module: Twitter::Unicode

Defined in:
lib/twitter-text/unicode.rb

Overview

This module lazily defines constants of the form Uxxxx for all Unicode codepoints from U0000 to U10FFFF. The value of each constant is the UTF-8 string for the codepoint. Examples:

copyright = Unicode::U00A9
euro = Unicode::U20AC
infinity = Unicode::U221E

Constant Summary collapse

CODEPOINT_REGEX = 
/^U_?([0-9a-fA-F]{4,5}|10[0-9a-fA-F]{4})$/

Class Method Summary collapse

Class Method Details

.const_missing(name) ⇒ Object 



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# File 'lib/twitter-text/unicode.rb', line 13

def self.const_missing(name)
  # Check that the constant name is of the right form: U0000 to U10FFFF
  if name.to_s =~ CODEPOINT_REGEX
    # Convert the codepoint to an immutable UTF-8 string,
    # define a real constant for that value and return the value
    #p name, name.class
    const_set(name, [$1.to_i(16)].pack("U").freeze)
  else  # Raise an error for constants that are not Unicode.
    raise NameError, "Uninitialized constant: Unicode::#{name}"
  end
end