this is broken, as you have below method with parameter. so it overwrite your reader:
```
irb
irb(main):001:0> def a()
irb(main):002:1> end
=> nil
irb(main):003:0> def a(a)
irb(main):004:1> end
=> nil
irb(main):005:0> a
ArgumentError: wrong number of arguments (0 for 1)
	from (irb):3:in `a'
	from (irb):5
	from /usr/bin/irb:12:in `<main>'
irb(main):006:0> 
```

In general I have suggestion to use below `def use_fadump=`. In such case you should always return same value you get and for unsupported case raise exception