Module: Tracksperanto::Safety

Included in:
Import::Base
Defined in:
lib/tracksperanto/safety.rb

Overview

Implements the safe_reader class method which will define (or override) readers that raise if ivar is nil

Instance Method Summary collapse

Instance Method Details

#safe_reader(*attributes) ⇒ Object

Inject a reader that checks for nil


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# File 'lib/tracksperanto/safety.rb', line 10

def safe_reader(*attributes)
  attributes.each do | an_attr |
    alias_method "#{an_attr}_without_nil_protection", an_attr
    define_method(an_attr) do
      val = send("#{an_attr}_without_nil_protection")
      raise "Expected #{an_attr} on #{self} not to be nil" if val.nil?
      val
    end
  end
end