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class ActiveSupport::Deprecation::DeprecatedConstantProxy

DeprecatedConstantProxy transforms a constant into a deprecated one. It takes the full names of an old (deprecated) constant and of a new constant (both in string form) and a deprecator. The deprecated constant now returns the value of the new one.

PLANETS = %w(mercury venus earth mars jupiter saturn uranus neptune pluto)

# (In a later update, the original implementation of `PLANETS` has been removed.)

PLANETS_POST_2006 = %w(mercury venus earth mars jupiter saturn uranus neptune)
PLANETS = ActiveSupport::Deprecation::DeprecatedConstantProxy.new("PLANETS", "PLANETS_POST_2006", ActiveSupport::Deprecation.new)

PLANETS.map { |planet| planet.capitalize }
# => DEPRECATION WARNING: PLANETS is deprecated! Use PLANETS_POST_2006 instead.
     (Backtrace information)
     ["Mercury", "Venus", "Earth", "Mars", "Jupiter", "Saturn", "Uranus", "Neptune"]

Inherits From

Public class methods

Source code GitHub
# File activesupport/lib/active_support/deprecation/proxy_wrappers.rb, line 121
def self.new(*args, **options, &block)
  object = args.first

  return object unless object
  super
end
Source code GitHub
# File activesupport/lib/active_support/deprecation/proxy_wrappers.rb, line 128
def initialize(old_const, new_const, deprecator, message: "#{old_const} is deprecated! Use #{new_const} instead.")
  Kernel.require "active_support/inflector/methods"

  @old_const = old_const
  @new_const = new_const
  @deprecator = deprecator
  @message = message
end

Public instance methods

Source code GitHub
# File activesupport/lib/active_support/deprecation/proxy_wrappers.rb, line 158
def append_features(base)
  @deprecator.warn(@message, caller_locations)
  base.include(target)
end

Returns the class of the new constant.

PLANETS_POST_2006 = %w(mercury venus earth mars jupiter saturn uranus neptune)
PLANETS = ActiveSupport::Deprecation::DeprecatedConstantProxy.new('PLANETS', 'PLANETS_POST_2006')
PLANETS.class # => Array
Source code GitHub
# File activesupport/lib/active_support/deprecation/proxy_wrappers.rb, line 154
def class
  target.class
end
Source code GitHub
# File activesupport/lib/active_support/deprecation/proxy_wrappers.rb, line 168
def extended(base)
  @deprecator.warn(@message, caller_locations)
  base.extend(target)
end

Don’t give a deprecation warning on inspect since test/unit and error logs rely on it for diagnostics.

Source code GitHub
# File activesupport/lib/active_support/deprecation/proxy_wrappers.rb, line 141
def inspect
  target.inspect
end
Source code GitHub
# File activesupport/lib/active_support/deprecation/proxy_wrappers.rb, line 163
def prepend_features(base)
  @deprecator.warn(@message, caller_locations)
  base.prepend(target)
end

Definition files