1-5-6.rkt

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0 0 24 29 1 #"\n"
0 9         145 21           0 0           0 23 0 24 3 1 #"("
0 0 15 3 6 #"define"
0 0 24 3 2 #" ("
0 0 14 3 2 #"x+"
0 0 24 3 1 #" "
0 0 14 3 1 #"p"
0 0 24 3 1 #")"
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0 0 24 3 3 #"  ("
0 0 14 3 9 #"make-posn"
0 0 24 3 2 #" ("
0 0 14 3 1 #"+"
0 0 24 3 2 #" ("
0 0 14 3 6 #"posn-x"
0 0 24 3 1 #" "
0 0 14 3 1 #"p"
0 0 24 3 2 #") "
0 0 21 3 1 #"3"
0 0 24 3 3 #") ("
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0 0 24 3 1 #" "
0 0 14 3 1 #"p"
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0           0 0 0 24 29 1 #"\n"
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0 0 17 3 21 #"; Posn Number -> Posn"
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0 0 15 3 6 #"define"
0 0 24 3 2 #" ("
0 0 14 3 9 #"posn-up-x"
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0 0 14 3 1 #"p"
0 0 24 3 1 #" "
0 0 14 3 1 #"n"
0 0 24 3 1 #")"
0 0 24 29 1 #"\n"
0 0 24 3 3 #"  ("
0 0 14 3 9 #"make-posn"
0 0 24 3 1 #" "
0 0 14 3 1 #"n"
0 0 24 3 2 #" ("
0 0 14 3 6 #"posn-y"
0 0 24 3 1 #" "
0 0 14 3 1 #"p"
0 0 24 3 3 #")))"
0 0 24 29 1 #"\n"
0 0 24 29 1 #"\n"
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#"; redefinition of x+ using the updater/functional setter above"
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0 0 24 3 3 #"  ("
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0 0 24 3 1 #" "
0 0 14 3 1 #"p"
0 0 24 3 2 #" ("
0 0 14 3 1 #"+"
0 0 24 3 1 #" "
0 0 21 3 1 #"3"
0 0 24 3 2 #" ("
0 0 14 3 6 #"posn-x"
0 0 24 3 1 #" "
0 0 14 3 1 #"p"
0 0 24 3 4 #"))))"
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0 0 24 29 1 #"\n"
0 0 24 29 1 #"\n"
0 0 24 29 1 #"\n"
0 0 24 3 1 #"("
0 0 15 3 13 #"define-struct"
0 0 24 3 1 #" "
0 0 14 3 3 #"ufo"
0 0 24 3 2 #" ["
0 0 14 3 3 #"loc"
0 0 24 3 1 #" "
0 0 14 3 3 #"vel"
0 0 24 3 2 #"])"
0 0 24 29 1 #"\n"
0 0 17 3 24 #"; A UFO is a structure: "
0 0 24 29 1 #"\n"
0 0 17 3 23 #";   (make-ufo Posn Vel)"
0 0 24 29 1 #"\n"
0 0 17 3 46 #"; interpretation (make-ufo p v) is at location"
0 0 24 29 1 #"\n"
0 0 17 3 24 #"; p moving at velocity v"
0 0 24 29 1 #"\n"
0 0 24 29 1 #"\n"
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0 0 24 3 2 #" ["
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0 0 14 3 6 #"deltay"
0 0 24 3 2 #"])"
0 0 24 29 1 #"\n"
0 0 17 3 24 #"; A Vel is a structure: "
0 0 24 29 1 #"\n"
0 0 17 3 28 #";   (make-vel Number Number)"
0 0 24 29 1 #"\n"
0 0 17 3 54 #"; interpretation (make-vel dx dy) means a velocity of "
0 0 24 29 1 #"\n"
0 0 17 3 47 #"; dx pixels [per tick] along the horizontal and"
0 0 24 29 1 #"\n"
0 0 17 3 51 #"; dy pixels [per tick] along the vertical direction"
0 0 24 29 1 #"\n"
0 0 24 29 1 #"\n"
0 0 24 29 1 #"\n"
0 0 17 3 12 #"; UFO -> UFO"
0 0 24 29 1 #"\n"
0 0 17 3 46 #"; determines where u moves in one clock tick; "
0 0 24 29 1 #"\n"
0 0 17 3 27 #"; leaves the velocity as is"
0 0 24 29 1 #"\n"
0 0 24 29 1 #"\n"
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0 0 21 3 1 #"8"
0 0 24 3 1 #" "
0 0 21 3 2 #"-3"
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0 0 14 3 8 #"make-vel"
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0 0 21 3 2 #"22"
0 0 24 3 1 #" "
0 0 21 3 2 #"80"
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0 0 21 3 2 #"30"
0 0 24 3 1 #" "
0 0 21 3 2 #"77"
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0 0 24 3 2 #" ("
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0 0 24 3 2 #" ("
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0 0 24 3 1 #" "
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0 0 24 3 1 #" "
0 0 14 3 2 #"u2"
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0 0 24 29 1 #"\n"
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0 0 14 3 8 #"make-ufo"
0 0 24 3 2 #" ("
0 0 14 3 9 #"make-posn"
0 0 24 3 1 #" "
0 0 21 3 2 #"17"
0 0 24 3 1 #" "
0 0 21 3 2 #"77"
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0 0 14 3 2 #"v2"
0 0 24 3 2 #"))"
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0 0 24 3 1 #" "
0 0 24 29 1 #"\n"
0 9         313 21           0 0           0 51 0 24 3 1 #"("
0 0 15 3 6 #"define"
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0 0 24 3 1 #" "
0 0 14 3 1 #"u"
0 0 24 3 1 #")"
0 0 24 29 1 #"\n"
0 0 24 3 3 #"  ("
0 0 14 3 8 #"make-ufo"
0 0 24 29 1 #"\n"
0 0 24 3 4 #"   ("
0 0 14 3 9 #"make-posn"
0 0 24 29 1 #"\n"
0 0 24 3 5 #"    ("
0 0 14 3 1 #"+"
0 0 24 3 2 #" ("
0 0 14 3 6 #"posn-x"
0 0 24 3 2 #" ("
0 0 14 3 7 #"ufo-loc"
0 0 24 3 1 #" "
0 0 14 3 1 #"u"
0 0 24 3 4 #")) ("
0 0 14 3 10 #"vel-deltax"
0 0 24 3 2 #" ("
0 0 14 3 7 #"ufo-vel"
0 0 24 3 1 #" "
0 0 14 3 1 #"u"
0 0 24 3 3 #")))"
0 0 24 29 1 #"\n"
0 0 24 3 5 #"    ("
0 0 14 3 1 #"+"
0 0 24 3 2 #" ("
0 0 14 3 6 #"posn-y"
0 0 24 3 2 #" ("
0 0 14 3 7 #"ufo-loc"
0 0 24 3 1 #" "
0 0 14 3 1 #"u"
0 0 24 3 4 #")) ("
0 0 14 3 10 #"vel-deltay"
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0 0 14 3 1 #"u"
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0           0 0 0 24 29 1 #"\n"
0 0 24 29 1 #"\n"
0 0 17 3 18 #"; Posn Vel -> Posn"
0 0 24 29 1 #"\n"
0 0 17 3 13 #"; adds v to p"
0 0 24 29 1 #"\n"
0 0 17 3 61
#"; (i.e. moves posn, traveling at velocity v, by one time unit"
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0 0 14 3 10 #"vel-deltax"
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0 0 14 3 1 #"p"
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0 0 14 3 10 #"vel-deltay"
0 0 24 3 1 #" "
0 0 14 3 1 #"v"
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0 0 24 29 1 #"\n"
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0 0 24 3 2 #" ("
0 0 14 3 5 #"posn+"
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0 0 14 3 2 #"p1"
0 0 24 3 1 #" "
0 0 14 3 2 #"v1"
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0 0 14 3 2 #"p2"
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0 0 24 29 1 #"\n"
0 0 24 3 1 #"("
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0 0 24 3 2 #" ("
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0 0 14 3 9 #"make-posn"
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0 0 24 3 1 #" "
0 0 21 3 2 #"77"
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0 0 24 29 1 #"\n"
0 0 24 29 1 #"\n"
0 0 17 3 28 #"; Redefinition of ufo-move-1"
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0 0 24 3 1 #"("
0 0 15 3 6 #"define"
0 0 24 3 2 #" ("
0 0 14 3 10 #"ufo-move-1"
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0 0 14 3 1 #"u"
0 0 24 3 3 #") ("
0 0 14 3 7 #"ufo-vel"
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0 0 14 3 1 #"u"
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0 0 24 29 1 #"\n"
0 0 24 3 4 #"   ("
0 0 14 3 7 #"ufo-vel"
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0 0 14 3 1 #"u"
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0 0 24 29 1 #"\n"
0           0