CSC151.02 2016S, Class 20: Collage - Copy and Paste
===================================================

_Overview_

* Preliminaries.
    * Admin.
    * Upcoming Work.
    * Extra Credit.
    * Questions.
* Lab.

Preliminaries
-------------

### Admin

* Continue partners (also HW partners).
* Friday PSA.
* Good luck ST!

### Reminders

* Office hours: MTWF 10-11, Tu 1-2.
    * Sign up at <http://rebelsky.youcanbook.me>.
    * Also feel free to stop by when my door is open.
    * Or to email me for an appointment.
* Tutor hours
    * Sunday, 3-5 p.m.
    * Sunday-Thursday, 7-10 p.m.
* Weekly review sessions:
    * Wednesday at 8pm in the CS Commons with 
    * No Thursday review session next week .... :-(
    * Thursday at 8pm in the CS Commons with 

### Upcoming Work:

* Reading for Monday
    * [Anonymous Procedures](../readings/anonymous-procedures-reading.html)
* [Assignment 5](../assignments/assignment.05.html) due next Tuesday
  at 10:30 p.m.
* No writeup today!

### Extra Credit

* Send your reports to <rebelsky@grinnell.edu> with subject 
  "CSC 151 Extra Credit".  (Do not include the quotation marks.)
* Send opportunities to me before class with subject
  "CSC 151 EXTRA CREDIT OPPORTUNITY!"

#### Academic / Artistic

* CS Table, Tuesday, Apple vs. the FBI.
* Met Opera Simulcast, Saturday, March 5.

#### Peer

* Too much tonight!  Try to do at least one of these things.
* Pun Club Tournament Friday the 26th 8pm under bob's.
* Contra Dance Friday the 26th 7:30-10:00 mainly in the main lounge
* AppDev Pub Night, Friday, 8pm-10pm, Lyle's (JRC Basement).
* Black History Month Showcase, Friday, Harris, 7:00-9:00 p.m.
  (JB performs aftger 8)
* 7:30 p.m Seven-Day Film Chalenge, in the Wall
* Improv Show the 27th 7:30 until we feel like we're done in Loose Lounge.
* Vote for SGA positions.
* Special Campus Council Meeting About Posse Situation, 4pm in ARH 102.

#### Regular Peer

* Social Dance Workshop Tuesdays 7:00-8:00 in Bucksbaum Dance Studio
* Pun club Saturdays at 4pm in Younker 
* Electronic Potpourri on KDIC Fridays at Five 
* Space Odyssey KDIC Fridays at Six

#### Misc

* Christine Tran show in Smith Gallery.

#### Far in the Future

* Lords of the Flies, April.

### No Extra Credit, But Still Good

* Regional diving at noon tomorrow.

### Questions

_Can you clarify the difference between test-case and test-suite._

> Both groups tests/checks together.

> test-suites are delayed; only run when you say `run-tests`

> test-cases, unless nested in test-suites, run immediately

> Irrelevant for today's quiz

_Is `cond` just like `if` but with extra brackets?_

> `cond` does more tests!

<pre>
> (define classify
    (lambda (number)
      (if (< number 60)
          'f
          (if (< number 70)
              'd
              (if (< number 80)
                  'c
                  'b)))))
> (classify 85)
'b
> (define classify
    (lambda (number)
      (cond
        [(< number 60)
         'f]
        [(< number 70)
         'd]
        [(< number 80)
         'c]
        [else
         'impossible])))
</pre>

_Why do I get #f for `(and (= 2 3) (/ 3 0))` but an error if I write
  `(and (= 2 2) (/ 3 0))`._

> `and` evaluates each expression in turn.  If the expression is false, 
  `and` returns immediately.  Otherwise, `and` moves on to the next 
  expression.  If any of the expressions it hits gives an error,
  `and` gives an error.

Quiz
----

Lab
---

No writeup today!