Class 12: Characters and Strings

Held: Friday, 7 February 2003

Summary: Today we consider two of Scheme's core data types: Characters and strings.

Related Pages:

• EBoard.
• Reading on Characters.
• Reading on Strings.
• Lab on Strings.

Assignments

Read CGI Scripting in Scheme.

Notes:

• I've heard some concern that it is difficult to finish most labs during class period. I'll work on shrinking the labs, but you should also make an effort to try to finish them outside of class. Tutors are available many evenings, and I answer email most evenings.
• I was talking to an alum of CS151, and that alum mentioned that CS151 often takes much more time than I expect. I'm willing to admit that I may significantly mis-estimate the amount of time work for this class takes. Hence, I would appreciate it if you would keep track (informally is fine) how long each thing you do for this class takes. I will distribute anonymous surveys weekly so I can judge how I'm doing.
• I have also been convinced that ten hours outside of class is too much to ask. Use seven hours per week of outside work as a cap. (The first thing to go should be assignments, and you should put a note at the top of an assignment saying "Hit the seven hour mark this week.") Believe it or not, but I do hope that most weeks you will spend less than that amount.
• Are there questions on conditionals?
• Are there questions on Lab writeup 1?

Overview:

• Short introduction to strings.
• Lab: Characters and Strings.

Characters and Strings

• Characters: The building blocks of strings
• Strings: Collections of characters
• Together: The basics types for input and output in Scheme
• CGI input and output: next class
• Other kinds of input and output: much later

Lab

• Do as much of the lab as you can.
• Reflect.