Interlude

Quiz 2 Review and Duscussion

CS 3540
Programming Languages and Paradigms

Today

Quiz 2 did not go as well as many of you had hoped. Rather than move forward in our discussion of variable bindings and scope, today we will:

• review one of the quiz problems,
• discuss programming strategy,
• put the quiz scores in context, and
• consider how we might improve going forward.

Solving a Problem

This is a map you can follow:

1. develop structure of code based data structure of input
2. choose return values based on data type of output
3. define values for base cases
4. solve parts of compound cases
   • decompose the argument based on the datatype
   • solve subexpressions with recursive calls
5. define values for compound cases by assembling answers for the parts
   • combine answers based on the return type

This is a rough map, not a fixed set of guaranteed steps.

Wrap Up

(This is the same as from last time.)

• Reading -- Read this short section on using let to name local functions. If functions in Racket are named like any other value, then let can do the job!
  
  Then read this short section on how boolean operators are syntactic abstractions of if expressions.


• Homework 7 is available and due on Friday.


• Quiz 2 extra credit is available and due on Tuesday.