语法看不懂，能帮忙解释一下吗？

etamina

下面的语句中ask patch和create-initial-turtles 后面接的[ ]中的语句是什么含义，其中非原语的都是定义的全局或者外部变量。语法有点奇怪，谁能帮我解释一下吗？多谢
# Q  W+ B6 U+ |- ito make-turtles
* H, O% d) z8 v+ J! h- s    ask patch 0 0 [
      create-initial-turtles num-random-min   "random-min"   violet
      create-initial-turtles num-random       "random"       brown
      create-initial-turtles num-random-away  "random-away"  pink
      create-initial-turtles num-open-min     "open-min"     blue
      create-initial-turtles num-open-min-max "open-min-max" orange ]
: p& O) n6 V9 z2 h! B  M6 M* D: O, b  set-common-variables
end
* R5 P# Y; S( V
9 B; @) H+ N3 hto create-initial-turtles [n turtle-rule turtle-color]
  ask n-of n (patches in-radius initial-radius with [not any? turtles-here])
  [ sprout 1
7 q* Q% M  {& s  I: g1 h6 Y! [: q& v    [ set rule turtle-rule
! j/ j/ ?% p2 {% L2 z3 E% L      set color turtle-color ] ]
: M0 |3 f$ r% Y2 J! B# p/ ]( Iend
8 ]) E- m: @9 f. r
[ 本帖最后由 etamina 于 2008-4-30 13:05 编辑 ]