method
private_method_defined?
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private_method_defined?(p1)
public
Returns true if the named private method is defined by _ mod_ (or its included modules and, if mod is a class, its ancestors).
module A def method1() end end class B private def method2() end end class C < B include A def method3() end end A.method_defined? :method1 #=> true C.private_method_defined? "method1" #=> false C.private_method_defined? "method2" #=> true C.method_defined? "method2" #=> false