Unicode Library for Ruby
     Version 0.4.4

    Yoshida Masato

• Introduction

  Unicode string manipulation library for Ruby. This library is based on UAX #15 Unicode Normalization Forms(*1).

  *1 <URL:http://www.unicode.org/unicode/reports/tr15/>

• Install

  This can work with ruby-1.8.7 or later. I recommend you to use ruby-1.9.3 or later.

  Make and install usually. For example, when Ruby supports dynamic linking on your OS,

  ruby extconf.rb
  make
  make install
  

  To install using gem, for exapmle:

  gem build unicdoe.gemspac
  gem install unicode
  

• Usage

  If you do not link this module with Ruby statically,

  require "unicode"
  

  before using.

• Module Functions

  All parameters of functions must be UTF-8 strings.

  Unicode::strcmp(str1, str2) Unicode::strcmp_compat(str1, str2)

  Compare Unicode strings with a normalization.
  strcmp uses the Normalization Form D, strcmp_compat uses
  Normalization Form KD.

  Unicode::decompose(str) Unicode::decompose_compat(str)

  Decompose Unicode string. Then the trailing characters
  are sorted in canonical order.
  decompose uses the canonical decomposition,
  decompose_compat uses the compatibility decomposition.
  The decomposition is based on the character decomposition
  mapping in UnicodeData.txt and the Hangul decomposition
  algorithm.

  Unicode::decompose_safe(str)

  Decompose Unicode string with a non-standard mapping.
  It does not decompose the characters in
  CompositionExclusions.txt.

  Unicode::compose(str)

  Compose Unicode string. Before composing, the trailing
  characters are sorted in canonical order.
  The parameter must be decomposed.
  The composition is based on the reverse of the
  character decomposition mapping in UnicodeData.txt,
  CompositionExclusions.txt and the Hangul composition
  algorithm.

  Unicode::normalize_D(str) (Unicode::nfd(str)) Unicode::normalize_KD(str) (Unicode::nfkd(str))

  Normalize Unicode string in form D or form KD.
  These are aliases of decompose/decompose_compat.

  Unicode::normalize_D_safe(str) (Unicode::nfd_safe(str))

  This is an alias of decompose_safe.

  Unicode::normalize_C(str) (Unicode::nfc(str)) Unicode::normalize_KC(str) (Unicode::nfkc(str))

  Normalize Unicode string in form C or form KC.
    normalize_C  = decompose + compose
    normalize_KC = decompose_compat + compose

  Unicode::normalize_C_safe(str) (Unicode::nfc_safe(str))

  Normalize Unicode string with decompose_safe.
    normalize_C_safe  = decompose_safe + compose
  

  Unicode::upcase(str) Unicode::downcase(str) Unicode::capitalize(str)

  Case conversion functions.
  The mappings that are used by these functions are not normative
  in UnicodeData.txt.

  Unicode::categories(str) Unicode::abbr_categories(str)

  Get an array of general category names of the string.
  get_abbr_categories returns abbreviated names.
  These can be called with a block.
  
    Unicode.get_category do |category| p category end
  

  Unicode::text_elements(str)

  Get an array of text elements.
  A text element is a unit that is displayed as a single character.
  These can be called with a block.

  Unicode::width(str[, cjk])

  Estimate the display width on the fixed pitch text terminal.
  It based on Markus Kuhn's mk_wcwidth.
  If the optional argument 'cjk' is true, East Asian
  Ambiguous characters are treated as wide characters.
  
    Unicode.width("\u03b1") #=> 1
    Unicode.width("\u03b1", true) #=> 2

• Bugs

  UAX #15 suggests that the look up for Normalization Form C should not be implemented with a hash of string for better performance.

• Copying

  This extension module is copyrighted free software by Yoshida Masato.

  You can redistribute it and/or modify it under the same term as Ruby.

• Author

  Yoshida Masato <yoshidam@yoshidam.net>

• History

  Feb 7, 2013 version 0.4.4 update unidata.map for Unicode 6.2 Aug 8, 2012 version 0.4.3 add categories, text_elements and width Feb 29, 2012 version 0.4.2 add decompose_safe Feb 3, 2012 version 0.4.1 update unidata.map for Unicode 6.1 Oct 14, 2010 version 0.4.0 fix the composition algorithm, and support Unicode 6.0 Feb 26, 2010 version 0.3.0 fix a capitalize bug and support SpecialCasing Dec 29, 2009 version 0.2.0 update for Ruby 1.9.1 and Unicode 5.2 Sep 10, 2005 version 0.1.2 update unidata.map for Unicode 4.1.0 Aug 26, 2004 version 0.1.1 update unidata.map for Unicode 4.0.1 Nov 23, 1999 version 0.1