Ruby Class Example: Box
# Box drawing class. class Box # Initialize to given size, and filled with spaces. def initialize(w,h) @wid = w @hgt = h @fill = ' ' end # Change the fill. def fill(f) @fill = f return self end # Rotate 90 degrees. def flip @wid, @hgt = @hgt, @wid return self end # Generate (print) the box def gen line('+', @wid - 2, '-') (@hgt - 2).times { line('|', @wid - 2, @fill) } line('+', @wid - 2, '-') end # For printing def to_s fill = @fill if fill == ' ' fill = '(spaces)' end return "Box " + @wid.to_s + "x" + @hgt.to_s + ", filled: " + fill end private # Print one line of the box. def line(ends, count, fill) print ends; count.times { print fill } print ends, "\n"; end end # Create some boxes. b1 = Box.new(10, 4) b2 = Box.new(5,12).fill('$') b3 = Box.new(3,3).fill('@') print "b1 = ", b1, "\nb2 = ", b2, "\nb3 = ", b3, "\n\n" # Print some boxes. print "b1:\n"; b1.gen print "\nb2:\n"; b2.gen print "\nb3:\n"; b3.gen print "\nb2 flipped and filled with #:\n"; b2.fill('#').flip.gen print "\nb2 = ", b2, "\n"