I read some of the sample code (the clock one) and I don't understand how
some of field scoping happens, I mean I don't understand from a Ruby point
of view. Here is the code (simplified):
01 Shoes.app :height => 260, :width => 250 do
02 @radius, @centerx, @centery = 90, 126, 140
03 stack :margin => 10 do
04 animate(8) do
05 @time = Time.now
06 clear do
07 draw_background
08 stack do
09 background black
10 para @time.strftime("%a"),
11 ....
12 end
13 end
14 clock_hand @time.sec + (@time.usec * 0.000001),2,30,red
15 ...
16 end
17 end
18 def draw_background
19 ...
20 end
21 def clock_hand(time, sw, unit=30, color=black)
22 ...
23 end
24 end
So,
(1) the '@time' field is defined in the block starting at line 3 and is
visible in the inner block starting at line 8
(2) the 'draw_background' method (could defined in the block starting at
line 1 using something like 'block.instance_eval(&block)') is also visible
in the inner blocks
How does all this magic happen? Is it happening in the C code? Is it
possible to play with blocks using pure Ruby?
Thanks,
Jean Lazarou
