Implements multibyte methods for easier access to multibyte characters in a String instance.

Methods
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Instance Public methods
chars()
# File activesupport/lib/active_support/core_ext/string/multibyte.rb, line 56
def chars
  ActiveSupport::Deprecation.warn('String#chars has been deprecated in favor of String#mb_chars.', caller)
  mb_chars
end
is_utf8?()

Returns true if the string has UTF-8 semantics (a String used for purely byte resources is unlikely to have them), returns false otherwise.

# File activesupport/lib/active_support/core_ext/string/multibyte.rb, line 51
def is_utf8?
  ActiveSupport::Multibyte::Chars.consumes?(self)
end
mb_chars()

Multibyte proxy

mb_charsis a multibyte safe proxy for string methods.

In Ruby 1.8 and older it creates and returns an instance of the ActiveSupport::Multibyte::Chars class which encapsulates the original string. A Unicode safe version of all the String methods are defined on this proxy class. If the proxy class doesn't respond to a certain method, it's forwarded to the encapsuled string.

name = 'Claus Müller'
name.reverse  #=> "rell??M sualC"
name.length   #=> 13
name.mb_chars.reverse.to_s   #=> "rellüM sualC"
name.mb_chars.length         #=> 12

In Ruby 1.9 and newer mb_charsreturns self because String is (mostly) encoding aware. This means that it becomes easy to run one version of your code on multiple Ruby versions.

Method chaining

All the methods on the Chars proxy which normally return a string will return a Chars object. This allows method chaining on the result of any of these methods.

name.mb_chars.reverse.length #=> 12

Interoperability and configuration

The Chars object tries to be as interchangeable with String objects as possible: sorting and comparing between String and Char work like expected. The bang! methods change the internal string representation in the Chars object. Interoperability problems can be resolved easily with a to_scall.

For more information about the methods defined on the Chars proxy see ActiveSupport::Multibyte::Chars. For information about how to change the default Multibyte behaviour see ActiveSupport::Multibyte.

# File activesupport/lib/active_support/core_ext/string/multibyte.rb, line 41
def mb_chars
  if ActiveSupport::Multibyte.proxy_class.wants?(self)
    ActiveSupport::Multibyte.proxy_class.new(self)
  else
    self
  end
end