TITLE: Ask Yourself, "What is the Pattern?"
AUTHOR: Eugene Wallingford
DATE: September 19, 2014  3:34 PM
DESC: 
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BODY:
I ran across this paragraph in an essay about
<A HREF="http://halfanhour.blogspot.ca/2006/08/things-you-really-need-to-learn.html">
   things you really need to learn in college</A>:

<BLOCKQUOTE><EM>
 Indeed, you should view the study of mathematics, history,
 science, and mechanics as the study of
 <A HREF="http://en.wikipedia.org/wiki/Archetype">
    archetypes</A>,
 basic patterns that you will recognize over and over.  But
 this means that, when you study these disciplines, you should
 be asking, "what is the pattern" (and not merely "what are
 the facts").  And asking this question will actually make
 these disciplines easier to learn.
</EM></BLOCKQUOTE>

Even in our intro course, I try to help students develop this
habit.  Rather than spending all of our time looking at syntax
and a laundry list of language features, I am introducing them
to some of the most basic code patterns, structures they will
encounter repeatedly as they solve problems at this level.
In week one came Input-Process-Output.  Then after learning
basic control structures, we encountered guarded actions,
range tests, running totals, sentinel loops, and "loop and a
half".  We encounter these patterns in the process of solving
problems.

While they are quite low-level, they are not merely idioms.
They are patterns every bit as much as patterns at the level
of the Gang of Four or PoSA.  They solve common problems,
recur in many forms, and are subject to trade-offs that
depend on the specific problem instance.

They compose nicely to create larger programs.  One of my goals
for next week is to have students solve new problems that allow
them to assemble programs from ideas they have already seen.
No new syntax or language features, just new problems.
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