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Ruby Build an Address Book in Ruby Class Design Contact Class: Part 1

Patrick Shushereba
Patrick Shushereba
10,911 Points
Posted by Patrick Shushereba
Patrick Shushereba
10,911 Points

Ruby address book question

I just had a quick question. In the exercise Build an Address Book, one of the lines is:

if !@middle_name.nil?

I completely missed the part about adding the exclamation point to the beginning. Can someone explain that to me?

1 Answer

Taylor Boudreau
Taylor Boudreau
7,285 Points
Taylor Boudreau
Taylor Boudreau
7,285 Points

Hi Patrick! I just did this myself. The ! means "not", so in this case you would read this as if the middle_name is not nil and contains some value return true and run the code, however if the middle_name is nil this would return false and the code would not be run.

Patrick Shushereba
Patrick Shushereba
10,911 Points
Patrick Shushereba
Patrick Shushereba
10,911 Points

Oh that makes so much sense. Thanks a lot.