Class String
In: lib/i18n/core_ext/string/interpolate.rb
Parent: Object

Extension for String class. This feature is included in Ruby 1.9 or later but not occur TypeError.

String#% method which accept "named argument". The translator can know the meaning of the msgids using "named argument" instead of %s/%d style.

Methods

%  

Constants

INTERPOLATION_PATTERN = Regexp.union( /%\{(\w+)\}/, # matches placeholders like "%{foo}" /%<(\w+)>(.*?\d*\.?\d*[bBdiouxXeEfgGcps])/ # matches placeholders like "%<foo>.d"
INTERPOLATION_PATTERN_WITH_ESCAPE = Regexp.union( /%%/, INTERPOLATION_PATTERN

External Aliases

size -> bytesize
  For older ruby versions, such as ruby-1.8.5
% -> interpolate_without_ruby_19_syntax

Public Instance methods

% uses self (i.e. the String) as a format specification and returns the result of applying it to the given arguments. In other words it interpolates the given arguments to the string according to the formats the string defines.

There are three ways to use it:

  • Using a single argument or Array of arguments.

    This is the default behaviour of the String class. See Kernel#sprintf for more details about the format string.

    Example:

      "%d %s" % [1, "message"]
      # => "1 message"
    
  • Using a Hash as an argument and unformatted, named placeholders.

    When you pass a Hash as an argument and specify placeholders with %{foo} it will interpret the hash values as named arguments.

    Example:

      "%{firstname}, %{lastname}" % {:firstname => "Masao", :lastname => "Mutoh"}
      # => "Masao Mutoh"
    
  • Using a Hash as an argument and formatted, named placeholders.

    When you pass a Hash as an argument and specify placeholders with %<foo>d it will interpret the hash values as named arguments and format the value according to the formatting instruction appended to the closing >.

    Example:

      "%<integer>d, %<float>.1f" % { :integer => 10, :float => 43.4 }
      # => "10, 43.3"
    

[Validate]