传递的方法名称与类的instance_methods之间没有匹配项

Question

I am getting the name of a method dynamically and I am passing it for a check like this:

if @myObject.class.instance_methods.include?(the_passed_method_name.to_sym) then
 # Something
else
 # Some other thing
end

lets say that I have passed "length" or "reverse" and I make the check for the class "String" and they work perfectly fine.But when I pass "bytesize" or "gsub" it doesn't accept it in the //Something code part.It thinks that "gsub" is not part of the instance methods of "String" which is not true because when I type this in irb:

"String".class.instance_methods.include?("gsub".to_sym)

it returns true . Can you give an advice ?

Answer 1

I am not sure what might be the problem, but I imagine there might be something wrong with your @myObject . Verify that it is actually a String object.

---

Some methods of interest that might make the code cleaner.

method_defined?

>>> String.method_defined? :gsub
true
>>> String.method_defined? :blah
false

respond_to? may be useful as well

myObj = "Test"

>>>myObj.class.method_defined? :gsub
true
>>>myObj.class.method_defined? :blah
false

>>>myObj.respond_to? :gsub
true
>>>myObj.respond_to? :blah
false