When refining a class (such as String in the following example) it is impossible to assign a constant. The constant will get attached to the module containing the refinement instead of the refined class. When inside of a refine block constants should get assigned to that class.
module Foobar
refine String do
FOO = "BAR"
def foobar
"foobar"
end
end
end
using Foobar
puts "".class::FOO # => uninitialized constant String::FOO (NameError)
puts "".foobar # => "foobar"
I would like to also mention that this impacts class_variables as well
module Foobar
@@baz = "boom"
refine String do
@@foo = "bar"
def foobar
@@foo
end
def bazical
@@baz
end
end
end
using Foobar
Foobar.class_variables #=> [:@@baz, :@@foo]
"".bazical #=> "boom"
"".foobar #=> "bar"
The first one I understand since the block can utilize variables and methods outside of itself. The second one really confuses me as I didn't expect it to skip over String and end up in Foobar. It also does not raise any warning about warning: class variable access from toplevel. Just as I would have expected constants to raise a SyntaxError for dynamic assignment. Instance variables seem to be ignored all together from what I can see.
Constants (and class variables) are not included in refinement modification. Constants still belong to outer class.
If we change this, we have to make incompatible change to constant scoping rules.
I don't think its wise.
But maybe above class variables case should be warned, probably.
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