Design Patterns Explained

CHAPTER 11
How Do Experts Design?
Overview
When trying to design, how do you start? Do you first get the
details and see how they are put together? Or do you look from the
big picture and break it down. Or is there another way?
Christopher Alexander's approach is to focus on the high-level relationships—
in a sense, working from the top down. Before making
any design decision, he feels it is essential to understand the context of
the problem we are solving. He uses patterns to define these relationships.
However, more than just presenting a collection of patterns,
he offers us an entire approach to design. The area about which he
is writing is architecture, designing places where people live and
work, but his principles apply to software design as well.
In this chapter,
• I discuss Alexander's approach to design.
• I describe how to apply this in the software arena.
Building by Adding Distinctions
In this chapter
Now that you have a handle on some of the design patterns, it is The Timeless Way
time to see how they can work together. For Alexander, it is not of Building: a book
enough to simply describe individual patterns. He uses them to about architecture
develop a new paradigm for design.
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