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Feature #3450

Updated by nahi (Hiroshi Nakamura) over 10 years ago

=begin 
  
  Is it intentional that the, undocumented, feature #442 (named arguments in format strings) ignores the Hash's default value?  
 
    >> hash = {greeting: 'Hello'}.tap{|h| h.default = 'World'} 
    >> '%{greeting}, %{greeted}' % hash 
    #=> KeyError: key{greeted} not found 
 
  It's quite common for templates to use default values. In interface localisation, untranslated strings may need to be substituted for the equivalent in the native language, or replaced with a generic string in the target language. When building reports with format strings, a default value of an empty string allows unexpanded format sequences to be non-fatal. In both cases, a default proc would provide even further flexibility. 
 
  Another perspective is that this behavior unnecessarily breaks the abstraction that default values are just like any other. 
 
 =end 
 

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