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class Module
# Encapsulates the common pattern of:
#
# alias_method :foo_without_feature, :foo
# alias_method :foo, :foo_with_feature
#
# With this, you simply do:
#
# alias_method_chain :foo, :feature
#
# And both aliases are set up for you.
#
# Query and bang methods (foo?, foo!) keep the same punctuation:
#
# alias_method_chain :foo?, :feature
#
# is equivalent to
#
# alias_method :foo_without_feature?, :foo?
# alias_method :foo?, :foo_without_feature?
#
# so you can safely chain foo, foo?, and foo! with the same feature.
def alias_method_chain(target, feature)
# Strip out punctuation on predicates or bang methods since
# e.g. target?_without_feature is not a valid method name.
aliased_target, punctuation = target.to_s.sub(/([?!])$/, ''), $1
alias_method "#{aliased_target}_without_#{feature}#{punctuation}", target
alias_method target, "#{aliased_target}_with_#{feature}#{punctuation}"
end
end
|
