32 lines
1.0 KiB
Racket
32 lines
1.0 KiB
Racket
#lang scribble/doc
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@(require scribble/manual
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(for-label scheme
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teachpack/htdp/elevator))
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@title[#:tag "elevator"]{Controlling an Elevator: elevator.ss}
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@declare-exporting[teachpack/htdp/elevator]
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The teachpack implements an elevator simulator.
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It displays an eight-floor elevator and accepts mouse clicks from the user,
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which are translated into service demands for the elevator.
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@defproc[(run [NextFloor number?]) any/c]{Creates an elevator simulator
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that is controlled by @scheme[NextFloor]. This function consumes the
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current floor, the direction in which the elevator is moving, and the
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current demands. From that, it computes where to send the elevator next.}
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Example: Define a function that consumes the current state of
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the elevator (three arguments) and returns a number between 1 and 8. Here
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is a non-sensical definition:
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@schemeblock[(define (controller x y z) 7)]
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It moves the elevator once, to the 7th floor.
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Second, set the teachpack to <code>elevator.ss</code>, click RUN, and
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evaluate
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@schemeblock[(run controller)]
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