minor

README.md

@@ -1,7 +1,7 @@
 Patty - A pattern matching library
 ==================================
 
-Patty is a library to perform pattern matching in Nim. The patterns have to be variant objects, which in Nim are encoded with a field (usually called `kind`) which varies in an enum, and a different object layout based on the value of this tag. An example would be
+Patty is a library to perform pattern matching in Nim. The patterns have to be [variant objects](http://nim-lang.org/docs/manual.html#types-object-variants), which in Nim are encoded with a field (usually called `kind`) which varies in an enum, and a different object layout based on the value of this tag. An example would be
 
 ```nim
 type
@@ -87,7 +87,7 @@ and expands to
 ```nim
 type
   ShapeE = enum
-    Circle, Rectangle
+    CircleE, RectangleE, UnitCircleE
   Shape = object
     case kind: ShapeE
     of CircleE:
@@ -115,7 +115,7 @@ A couple of limitations fo the `adt` macro:
 * field names must be unique across branches (that is, different variants cannot have two fields with the same name). This is actually a limitation of Nim.
 * the shortcut that groups field names by type does not seem to work, that is, in the above example one could not write `Rectangle(w, h: float)`.
 
-In the future, Patty will also add a proper definition of equality.
+In the future, Patty will also add a proper definition of equality and copy constructors. Also, some work needs to be done to make it easier to use the generated contructors with `ref` types, in particular for the important case of recursive algebraic data types.
 
 Things that do not work (yet)
 -----------------------------
@@ -236,7 +236,7 @@ match c:
     echo "hello ", name
 ```
 
-* or combinations of patterns
+* combining patterns with `or`
 
 ```nim
 match c:

test.nim

@@ -1,4 +1,4 @@
-import unittest, patty
+import unittest, patty, macros
 
 
 suite "adt construction":
@@ -41,6 +41,19 @@ suite "adt construction":
     let c = UnitCircle()
     check c.kind == UnitCircleE
 
+  test "recusive types":
+    adt IntList:
+      Nil
+      Cons(head: int, tail: ref IntList)
+
+    proc inew[A](a: A): ref A =
+      new(result)
+      result[] = a
+
+    var d = Cons(3, inew(Cons(2, inew(Cons(1, inew(Nil()))))))
+    check d.head == 3
+    check d.tail.head == 2
+
 suite "pattern matching":
   type
     ShapeKind = enum