2 files changed, 5 insertions, 2 deletions
diff --git a/chapter17/src/main/java/com/seaofnodes/simple/Parser.java b/chapter17/src/main/java/com/seaofnodes/simple/Parser.java
index 47e7c3bb..dae3cd54 100644
--- a/chapter17/src/main/java/com/seaofnodes/simple/Parser.java
+++ b/chapter17/src/main/java/com/seaofnodes/simple/Parser.java
@@ -335,7 +335,8 @@ public class Parser {
             int old = pos(nextPos);
             if( !peek(')') )
               parseAsgn(null,false);
-            assert pos() == nextEnd;
+            if( pos() != nextEnd )
+                throw errorSyntax( "Unexpected code after expression" );
             pos(old);
         }
 
@@ -691,7 +692,8 @@ public class Parser {
         if( id==null )
             return posT(old1);  // Reset lexer to reparse
         // Yes a forward ref, so declare it
-        TYPES.put(tname,t1);
+        Type t2 = t1 instanceof TypeMemPtr tmp ? tmp.makeFrom(false): t1;
+        TYPES.put(tname,t2);
         return t1;
     }
 
diff --git a/chapter17/src/main/java/com/seaofnodes/simple/type/TypeMemPtr.java b/chapter17/src/main/java/com/seaofnodes/simple/type/TypeMemPtr.java
index 08e7db1c..786a7be5 100644
--- a/chapter17/src/main/java/com/seaofnodes/simple/type/TypeMemPtr.java
+++ b/chapter17/src/main/java/com/seaofnodes/simple/type/TypeMemPtr.java
@@ -34,6 +34,7 @@ public class TypeMemPtr extends Type {
     public static TypeMemPtr make(TypeStruct obj, boolean nil) { return new TypeMemPtr(obj, nil).intern(); }
     public static TypeMemPtr make(TypeStruct obj) { return make(obj, false); }
     public TypeMemPtr makeFrom(TypeStruct obj) { return obj==_obj ? this : make(obj, _nil); }
+    public TypeMemPtr makeFrom(boolean nil) { return nil==_nil ? this : make(_obj, nil); }
     @Override public TypeMemPtr makeRO() { return makeFrom(_obj.makeRO()); }
     @Override public boolean isFinal() { return _obj.isFinal(); }