require 'test/unit' $KCODE = 'none' class TestDefined < Test::Unit::TestCase class Foo def foo p :foo end protected :foo def bar(f) yield(defined?(self.foo)) yield(defined?(f.foo)) end end def defined_test return !defined?(yield) end def test_defined $x = nil assert(defined?($x)) # global variable assert_equal('global-variable', defined?($x))# returns description foo=5 assert(defined?(foo)) # local variable assert(defined?(::Array)) # constant !! Array -> ::Array assert(defined?(Object.new)) # method assert(!defined?(Object.print)) # private method assert(defined?(1 == 2)) # operator expression f = Foo.new assert_nil(defined?(f.foo)) f.bar(f) { |v| assert(v) } assert(defined_test) # not iterator assert(!defined_test{}) # called as iterator end end