Module: Corefines::Object::ThenIf

Defined in:
lib/corefines/object.rb

Instance Method Summary collapse

Instance Method Details

#then_if(*conditions) {|self| ... } ⇒ Object

Returns self if self or any of the conditions evaluates to false, otherwise returns the evaluation of the block.

Each condition may be of the type:

  • Symbol - name of the method to be invoked using public_send.
  • Array - name of the method followed by arguments to be invoked using public_send.
  • Proc - proc to be called with self as the argument.
  • Any other object to be evaluated as true, or false.

Examples:

"foo".then_if(:empty?) { "N/A" } # => "foo"
   "".then_if(:empty?) { "N/A" } # => "N/A"

Parameters:

  • *conditions —

    conditions to evaluate.

Yields:

  • (self) —

    gives self to the block.

Returns:

  • (Object) —

    evaluation of the block, or self if any condition evaluates to false, or no condition given and self evaluates to false.



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# File 'lib/corefines/object.rb', line 267

module ThenIf
  refine ::Object do
    def then_if(*conditions)
      return self if conditions.empty? && !self
      return self unless conditions.all? do |arg|
        case arg
        when ::Symbol then public_send(arg)
        when ::Array then public_send(*arg)
        when ::Proc then arg.call(self)
        else arg
        end
      end
      yield self
    end
  end
end