completed book examples

book/examples/chapter8/GeometryEng.gf

@@ -1,4 +1,4 @@
---# -path=alltenses
+--# -path=.:present
 
 concrete GeometryEng of Geometry = LogicEng ** 
   open SyntaxEng, ParadigmsEng in {

book/examples/chapter8/Graftal.gf

@@ -0,0 +1,7 @@
+-- (c) Krasimir Angelov 2009
+abstract Graftal = {
+  cat N; S;
+  fun z : N ;
+      s : N -> N ;
+      c : N -> S ;
+  }

book/examples/chapter8/Sierpinski.gf

@@ -0,0 +1,16 @@
+concrete Sierpinski of Graftal = {
+  lincat N = {a : Str; b : Str} ;
+  lincat S = {s : Str} ;
+
+  lin z = {a = A; b = B} ;
+  lin s x = {
+    a = x.b ++ R ++ x.a ++ R ++ x.b ; 
+    b = x.a ++ L ++ x.b ++ L ++ x.a
+    } ;
+  lin c x = {s = "newpath 300 550 moveto" ++ x.a ++ "stroke showpage"} ;
+
+  oper A : Str = "0 2 rlineto" ;
+  oper B : Str = "0 2 rlineto" ;
+  oper L : Str = "+60 rotate" ;
+  oper R : Str = "-60 rotate" ;
+}