Add higher-order-functions and some other goodies

  * The reads clause now needs to be self framing.

  * The requires clause now needs to be framed by the reads clause.

  * There are one-shot lambdas, with a single arrow, but they will probably be
    removed.

  * There is a {:heapQuantifier} attribute to quantifiers, but they will
    probably be removed.

  * Add smart handling of type variables

  * Add < and > for datatype & type parameter

1 files changed, 20 insertions, 0 deletions

diff --git a/Test/hofs/Types.dfy b/Test/hofs/Types.dfy
new file mode 100644
index 00000000..9f62763a
--- /dev/null
+++ b/Test/hofs/Types.dfy
@@ -0,0 +1,20 @@
+// RUN: %dafny /compile:0 /print:"%t.print" "%s" > "%t"
+// RUN: %diff "%s.expect" "%t"
+
+method FnEqGhost<A>() {
+  ghost var f : A -> A -> A;
+  ghost var g : A -> (A -> A);
+  ghost var h : (A -> A) -> A;
+  ghost var b1 := f == g; // type checking should be ok
+  ghost var b2 := f == h; // type checking should fail
+
+  ghost var z;
+  ghost var b3 := f == z; // unify in progress
+  ghost var b4 := g == z; // should now be ok
+  ghost var b5 := h == z; // should now fail
+
+  ghost var zz;
+  ghost var b6 := h == zz; // unify in progress
+  ghost var b7 := g == zz; // should fail
+}
+