caac996acd
New structure groups all ADT modules under adt/ directory, removing redundant adt- prefix from filenames. Library names now read as (pacman-project adt position) etc. All imports updated accordingly. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
51 lines
1.6 KiB
Racket
51 lines
1.6 KiB
Racket
#lang r7rs
|
|
|
|
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
|
|
;; Position ADT ;;
|
|
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
|
|
|
|
;; A position represents a location on the logical maze grid.
|
|
;; Coordinates are in grid units (row, col), NOT pixels.
|
|
|
|
(define-library (pacman-project adt position)
|
|
(import (scheme base))
|
|
(export make-position)
|
|
|
|
(begin
|
|
|
|
;; make-position :: number, number -> position
|
|
;; Creates a new position object with row and column on the grid.
|
|
(define (make-position row col)
|
|
|
|
;; row! :: number -> /
|
|
(define (row! new-row)
|
|
(set! row new-row))
|
|
|
|
;; col! :: number -> /
|
|
(define (col! new-col)
|
|
(set! col new-col))
|
|
|
|
;; equal? :: position -> boolean
|
|
;; Checks whether two positions have the same coordinates.
|
|
(define (equal? other)
|
|
(and (= row (other 'row))
|
|
(= col (other 'col))))
|
|
|
|
;; move :: number, number -> position
|
|
;; Returns a new position shifted by delta-row and delta-col.
|
|
(define (move delta-row delta-col)
|
|
(make-position (+ row delta-row)
|
|
(+ col delta-col)))
|
|
|
|
;; dispatch-position :: symbol -> any
|
|
(define (dispatch-position msg)
|
|
(cond ((eq? msg 'row) row)
|
|
((eq? msg 'col) col)
|
|
((eq? msg 'row!) row!)
|
|
((eq? msg 'col!) col!)
|
|
((eq? msg 'equal?) equal?)
|
|
((eq? msg 'move) move)
|
|
(else (error "Position ADT -- Unknown message:" msg))))
|
|
|
|
dispatch-position)))
|