morpho in tutorial

doc/tutorial/MorphoEng.gf

@@ -0,0 +1,33 @@
+--# -path=.:prelude
+
+resource MorphoEng = open Prelude in {
+
+    param
+      Number = Sg | Pl ;
+
+    oper
+      Noun, Verb : Type = {s : Number => Str} ;
+
+      mkNoun : Str -> Str -> Noun = \x,y -> {
+        s = table {
+          Sg => x ;
+          Pl => y
+          }
+        } ;
+
+      regNoun : Str -> Noun = \s -> case last s of {
+        "s" | "z" => mkNoun s (s + "es") ;
+        "y"       => mkNoun s (init s + "ies") ;
+        _         => mkNoun s (s + "s")
+        } ;
+
+      mkVerb : Str -> Str -> Verb = \x,y -> mkNoun y x ;
+
+      regVerb : Str -> Verb = \s -> case last s of {
+        "s" | "z" => mkVerb s (s + "es") ;
+        "y"       => mkVerb s (init s + "ies") ;
+        "o"       => mkVerb s (s + "es") ;
+        _         => mkVerb s (s + "s")
+        } ;
+
+  }