I'm using method_missing
to define a class for namespacing constants in a vocabulary. To be effective, I need the vocabulary class to inherit from BasicObject
, otherwise none of the standard object methods are available as vocabulary terms (because the method isn't missing :). However, when I inherit from BasicObject
, I find I can't call utility methods in another module. The following code illustrates the issue in condensed form:
module Foo
class Bar
def self.fubar( s )
"#{s} has been fubar'd"
end
end
end
class V1
def self.method_missing( name )
Foo::Bar.fubar( "#{name} in v1" )
end
end
class V2 < BasicObject
def self.method_missing( name )
Foo::Bar.fubar( "#{name} in v2" )
end
end
# this works
puts V1.xyz
# => xyz in v1 has been fubar'd
# this doesn't
puts V2.xyz
# => NameError: uninitialized constant V2::Foo
What would I need to add to V2
so that it doesn't produce an unitialized constant error when I try to call the helper module?
It works if you change the method in V2
like this so that name resolution starts in the global scope.
def self.method_missing( name )
::Foo::Bar.fubar( "#{name} in v2" )
end
I looked it up in the documentation for you :
BasicObject does not include Kernel (for methods like puts) and BasicObject is outside of the namespace of the standard library so common classes will not be found without a using a full class path. ... Access to classes and modules from the Ruby standard library can be obtained in a BasicObject subclass by referencing the desired constant from the root like ::File or ::Enumerator.
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