Class: Module

Inherits:
Object
  • Object
show all
Defined in:
lib/everythingrb/core/module.rb

Instance Method Summary collapse

Instance Method Details

#attr_predicate(*attributes) ⇒ nil

Creates predicate (boolean) methods for instance variables Similar to attr_reader, attr_writer, etc.

Examples:

class User
  attr_predicate :admin, :active
end

user.admin? # => true/false based on @admin

Parameters:

  • *attributes (Array<Symbol, String>) —

    Instance variable names

Returns:

  • (nil) 


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# File 'lib/everythingrb/core/module.rb', line 18

def attr_predicate(*attributes)
  attributes.each do |attribute|
    module_eval <<-STR, __FILE__, __LINE__ + 1
      def #{attribute}?
        !!instance_variable_get("@#{attribute}")
      end
    STR
  end

  nil
end