CSC151.02 2013F, Class 06: Drawings as Values, Continued
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_Overview_

* Preliminaries
    * Admin.
    * Quick homework notes.
    * Clicker Questions.
* A bit more on drawings.
* Lab.
* Reflection.
* Looking ahead to procedures.

_Admin_

* We will continue the lab from Friday.
* I'm still working on getting HW1 reviewed.  Time is a very limited commodity
  (as I think you all know from your own experience).
* Note: Sometimes the html versions of the eboards don't get updated 
  right after class.  You can always see what I typed by going to the 
  original source.
* Study break, tonight, 8pm, CS commons
* Reminder: Mentor sessions are Thursdays and Sundays at 7:30 pm
* Readings for Tuesday 
    * Reread: Writing Your Own Procedures
    * Add: How Scheme Evaluates Expressions (Take 2)
* EC Opportunities:
    * Humanities Center Speaker Sarah Hendron
      Wed., Sept. 11, 7:30 p.m., JRC101
      Waking the Machines: Art, Design, and Adaptive Technology
    * CS Table next Friday (Reflections on Trusting Trust; NYT on NSA)
    * Other?

_Homework Questions_

* Should we use procedures?  **No!**

_Clicker Questions_

* Some questions on drawings
* Why is the drawing black not blue?

        #lang racket
        (require gigls/unsafe)
        (define d1 (drawing-scale drawing-unit-circle 15))
        (drawing-recolor d1 "blue")
        (define d2 (drawing-recolor (drawing-vshift d1 20) "red"))
        (define d3 (drawing-group d1 d2))
        (image-show (drawing->image d3 40 40))

    * Because drawing-recolor creates a *new* circle, it doesn't affect
      the other one

        (define x 5)
        (square x)
        x
A bit more on drawings
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Lab
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Reflection
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Looking ahead to procedures
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