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Text File | 1994-01-10 | 2.0 KB | 55 lines | [TEXT/GADA] |
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- --------------------------------------------------------------------
- --| Package : Spider |
- --------------------------------------------------------------------
- --| Abstract : |
- --| This package provides procedures to emulate "Spider" |
- --| primitives. The spider is a robot who can move around |
- --| the screen drawing simple patterns. |
- --| |
- --------------------------------------------------------------------
- --| File : spider.ads Version : 1.0 |
- --| Compiler/System : Alsys ADa |
- --| Author : John Dalbey Date : 9/18/92 |
- --------------------------------------------------------------------
-
- PACKAGE Spider IS
-
- TYPE Switch IS (on,off); -- boolean type
- TYPE ScreenColors IS (red, blue, green, black); -- available colors
-
- PROCEDURE Reset;
- -- Draw the Spider's room on the screen and put the spider in the center.
-
- PROCEDURE Start;
- -- Draw a random size room on the screen and put the spider in the
- -- upper left corner.
-
- -- Change the color of ink with which the spider draws
- PROCEDURE Blue;
- PROCEDURE Green;
- PROCEDURE Red;
- PROCEDURE Black;
-
- PROCEDURE Step;
- -- Take one step forward in the direction the spider is facing.
- -- EXCEPTIONS: Hit_the_Wall is raised if you try to step into a wall.
-
- PROCEDURE Turn;
- -- Turn 90 degrees to the right.
-
- FUNCTION AtWall return boolean;
- -- Return TRUE if the spider is standing next to a wall (edge of the room)
- -- and facing it.
-
- PROCEDURE Quit;
- -- End the drawing
-
- PROCEDURE Debug (Setting: Switch);
- -- Turn on or off single stepping through the program.
-
- FUNCTION Debug RETURN Boolean;
- -- Return current debug setting.
-
- END Spider;
-