U U extends Ruby’s Unicode support. It provides a string class called U::String with an interface that mimics that of the String class in Ruby 2.0, but that can also be used from both Ruby 1.8. This interface also has more complete Unicode support and never modifies the receiver. Thus, a U::String is an immutable value object. U comes with complete and very accurate documentation¹. The documentation can realistically also be used as a reference to the Ruby String API and may actually be preferable, as it’s a lot more explicit and complete than the documentation that comes with Ruby. ¹ See http://disu.se/software/u-1.0/api/ § Installation Install u with % gem install u § Usage Usage is basically the following: require 'u-1.0' a = 'äbc' a.upcase # ⇒ 'äBC' a.u.upcase # ⇒ 'ÄBC' That is, you require the library, then you invoke #u on a String. This’ll give you a U::String that has much better Unicode support than a normal String. It’s important to note that U only uses UTF-8, which means that #u will try to #encode the String as such. This shouldn’t be an issue in most cases, as UTF-8 is now more or less the universal encoding – and rightfully so. As U::Strings¹ are immutable value objects, there’s also a U::Buffer² available for building U::Strings efficiently. See the API³ for more complete usage information. The following sections will only cover the extensions and differences that U::String exhibit from Ruby’s built-in String class. ¹ See http://disu.se/software/u-1.0/api/U/String/ ² See http://disu.se/software/u-1.0/api/U/Buffer/ ³ See http://disu.se/software/u-1.0/api/ § Unicode Properties There are quite a few property-checking interrogators that let you check if all characters in a U::String have the given Unicode property: • #alnum?¹ • #alpha?² • #assigned?³ • #case_ignorable?⁴ • #cased?⁵ • #cntrl?⁶ • #defined?⁷ • #digit?⁸ • #graph?⁹ • #newline?¹⁰ • #print?¹¹ • #punct?¹² • #soft_dotted?¹³ • #space?¹⁴ • #title?¹⁵ • #valid?¹⁶ • #wide?¹⁷ • #wide_cjk?¹⁸ • #xdigit?¹⁹ • #zero_width?²⁰ ¹ See http://disu.se/software/u-1.0/api/U/String/#alnum-p-instance-method ² See http://disu.se/software/u-1.0/api/U/String/#alpha-p-instance-method ³ See http://disu.se/software/u-1.0/api/U/String/#assigned-p-instance-method ⁴ See http://disu.se/software/u-1.0/api/U/String/#case_ignorable-p-instance-method ⁵ See http://disu.se/software/u-1.0/api/U/String/#cased-p-instance-method ⁶ See http://disu.se/software/u-1.0/api/U/String/#cntrl-p-instance-method ⁷ See http://disu.se/software/u-1.0/api/U/String/#defined-p-instance-method ⁸ See http://disu.se/software/u-1.0/api/U/String/#digit-p-instance-method ⁹ See http://disu.se/software/u-1.0/api/U/String/#graph-p-instance-method ¹⁰ See http://disu.se/software/u-1.0/api/U/String/#newline-p-instance-method ¹¹ See http://disu.se/software/u-1.0/api/U/String/#print-p-instance-method ¹² See http://disu.se/software/u-1.0/api/U/String/#punct-p-instance-method ¹³ See http://disu.se/software/u-1.0/api/U/String/#soft_dotted-p-instance-method ¹⁴ See http://disu.se/software/u-1.0/api/U/String/#space-p-instance-method ¹⁵ See http://disu.se/software/u-1.0/api/U/String/#title-p-instance-method ¹⁶ See http://disu.se/software/u-1.0/api/U/String/#valid-p-instance-method ¹⁷ See http://disu.se/software/u-1.0/api/U/String/#wide-p-instance-method ¹⁸ See http://disu.se/software/u-1.0/api/U/String/#wide_cjk-p-instance-method ¹⁹ See http://disu.se/software/u-1.0/api/U/String/#xdigit-p-instance-method ²⁰ See http://disu.se/software/u-1.0/api/U/String/#zero_width-p-instance-method Similar to these methods are • #folded?¹ • #lower?² • #upper?³ which check whether a ‹U::String› has been cased in a given manner. ¹ See http://disu.se/software/u-1.0/api/U/String/#folded-p-instance-method ² See http://disu.se/software/u-1.0/api/U/String/#lower-p-instance-method ³ See http://disu.se/software/u-1.0/api/U/String/#upper-p-instance-method There’s also a #normalized?¹ method that checks whether a ‹U::String› has been normalized on a given form. ¹ See http://disu.se/software/u-1.0/api/U/String/#normalized-p-instance-method You can also access certain Unicode properties of the characters of a U::String: • #canonical_combining_class¹ • #general_category² • #grapheme_break³ • #line_break⁴ • #script⁵ • #word_break⁶ ¹ See http://disu.se/software/u-1.0/api/U/String/#canonical_combining_class-instance-method ² See http://disu.se/software/u-1.0/api/U/String/#general_category-instance-method ³ See http://disu.se/software/u-1.0/api/U/String/#grapheme_break-instance-method ⁴ See http://disu.se/software/u-1.0/api/U/String/#line_break-instance-method ⁵ See http://disu.se/software/u-1.0/api/U/String/#script-instance-method ⁶ See http://disu.se/software/u-1.0/api/U/String/#word_break-instance-method § Locale-specific Comparisons Comparisons of U::Strings respect the current locale (and also allow you to specify a locale to use): ‹#<=>›¹, #casecmp², and #collation_key³. ¹ See http://disu.se/software/u-1.0/api/U/String/#comparison-operator ² See http://disu.se/software/u-1.0/api/U/String/#casecmp-instance-method ³ See http://disu.se/software/u-1.0/api/U/String/#collation_key-instance-method § Additional Enumerators There are a couple of additional enumerators in #each_grapheme_cluster¹ and #each_word² (along with aliases #grapheme_clusters³ and #words⁴). ¹ See http://disu.se/software/u-1.0/api/U/String/#each_grapheme_cluster-instance-method ² See http://disu.se/software/u-1.0/api/U/String/#each_word-instance-method ³ See http://disu.se/software/u-1.0/api/U/String/#grapheme_clusters-instance-method ⁴ See http://disu.se/software/u-1.0/api/U/String/#words-instance-method § Unicode-aware Sub-sequence Removal #Chomp¹, #chop², #lstrip³, #rstrip⁴, and #strip⁵ all look for Unicode newline and space characters, rather than only ASCII ones. ¹ See http://disu.se/software/u-1.0/api/U/String/#chomp-instance-method ² See http://disu.se/software/u-1.0/api/U/String/#chop-instance-method ³ See http://disu.se/software/u-1.0/api/U/String/#lstrip-instance-method ⁴ See http://disu.se/software/u-1.0/api/U/String/#rstrip-instance-method ⁵ See http://disu.se/software/u-1.0/api/U/String/#strip-instance-method § Unicode-aware Conversions Case-shifting methods #downcase¹ and #upcase² do proper Unicode casing and the interface is further augmented by #foldcase³ and #titlecase⁴. #Mirror⁵ and #normalize⁶ do conversions similar in nature to the case-shifting methods. ¹ See http://disu.se/software/u-1.0/api/U/String/#downcase-instance-method ² See http://disu.se/software/u-1.0/api/U/String/#upcase-instance-method ³ See http://disu.se/software/u-1.0/api/U/String/#foldcase-instance-method ⁴ See http://disu.se/software/u-1.0/api/U/String/#titlecase-instance-method ⁵ See http://disu.se/software/u-1.0/api/U/String/#mirror-instance-method ⁶ See http://disu.se/software/u-1.0/api/U/String/#normalize-instance-method § Width Calculations #Width¹ will return the number of cells on a terminal that a U::String will occupy. #Center², #ljust³, and #rjust⁴ deal in width rather than length, making them much more useful for generating terminal output. #%⁵ (and its alias #format⁶) similarly deal in width. ¹ See http://disu.se/software/u-1.0/api/U/String/#width-instance-method ² See http://disu.se/software/u-1.0/api/U/String/#center-instance-method ³ See http://disu.se/software/u-1.0/api/U/String/#ljust-instance-method ⁴ See http://disu.se/software/u-1.0/api/U/String/#rjust-instance-method ⁵ See http://disu.se/software/u-1.0/api/U/String/#modulo-operator ⁶ See http://disu.se/software/u-1.0/api/U/String/#format-instance-method § Extended Type Conversions Finally, #hex¹, #oct², and #to_i³ use Unicode alpha-numerics for their respective conversions. ¹ See http://disu.se/software/u-1.0/api/U/String/#hex-instance-method ² See http://disu.se/software/u-1.0/api/U/String/#oct-instance-method ³ See http://disu.se/software/u-1.0/api/U/String/#to_i-instance-method § News § 1.0.0 Initial public release! § Financing Currently, most of my time is spent at my day job and in my rather busy private life. Please motivate me to spend time on this piece of software by donating some of your money to this project. Yeah, I realize that requesting money to develop software is a bit, well, capitalistic of me. But please realize that I live in a capitalistic society and I need money to have other people give me the things that I need to continue living under the rules of said society. So, if you feel that this piece of software has helped you out enough to warrant a reward, please PayPal a donation to now@disu.se¹. Thanks! Your support won’t go unnoticed! ¹ Send a donation: https://www.paypal.com/cgi-bin/webscr?cmd=_donations&business=now@disu.se&item_name=U § Reporting Bugs Please report any bugs that you encounter to the {issue tracker}¹. ¹ See https://github.com/now/u/issues § Authors Nikolai Weibull wrote the code, the tests, the documentation, and this README. § Licensing U is free software: you may redistribute it and/or modify it under the terms of the {GNU Lesser General Public License, version 3}¹ or later², as published by the {Free Software Foundation}³. ¹ See http://disu.se/licenses/lgpl-3.0/ ² See http://gnu.org/licenses/ ³ See http://fsf.org/