Chars enables you to work transparently with UTF-8 encoding in the Ruby String class without having extensive knowledge about the encoding. A Chars object accepts a string upon initialization and proxies String methods in an encoding safe manner. All the normal String methods are also implemented on the proxy.
String methods are proxied through the Chars object, and can be accessed through the
mb_chars method. Methods which would normally return a String object now return a Chars object so methods can be chained.
'The Perfect String '.mb_chars.downcase.strip.normalize # => "the perfect string"
Chars objects are perfectly interchangeable with
String objects as long as no explicit class
checks are made. If certain methods do explicitly check the class, call
to_s before you pass chars objects to them.
bad.explicit_checking_method 'T'.mb_chars.downcase.to_s
The default Chars implementation assumes that the encoding of the string is UTF-8, if you want to handle different encodings you can write your own multibyte string handler and configure it through ActiveSupport::Multibyte.proxy_class.
class CharsForUTF32
def size
@wrapped_string.size / 4
end
def self.accepts?(string)
string.length % 4 == 0
end
end
ActiveSupport::Multibyte.proxy_class = CharsForUTF32