To conclude this lesson, I want to discuss the
concept of negative design patterns, that is, patterns that should
be avoided. Interestingly, negative patterns were also mentioned in
Christopher Alexander's book, so in the first formulation of patterns.
So negative design pattern are basically guidelines on how
not to do things. In consoles with patterns, the guidelines
on how to do things. So basically, what the negative
design patterns do is, they enable recurring design defects to
be avoided. And as we will see in this class extensively,
in mini-course four, negative patterns are
also called anti-patterns or bad smells,
or bad code smells. So in mini-course four we will see several
examples of bad smells and what we can do to eliminate them.