Merge commit 'df5c5f5'

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diff --git a/Test/wishlist/sequences-s0-in-s.dfy b/Test/wishlist/sequences-s0-in-s.dfy
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+++ b/Test/wishlist/sequences-s0-in-s.dfy
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+// RUN: %dafny /compile:0 /autoTriggers:1 /print:"%t.print" /dprint:"%t.dprint" "%s" > "%t"

+// RUN: %diff "%s.expect" "%t"

+

+// The following is also due to a weakness in the axiomatization: namely, it is

+// not easy to learn, using Dafny's axioms, that s[0] in s. One can of course

+// prove it, but it doesn't come for free.

+

+method InSeqTriggers(s: seq<int>, i: nat)

+  requires forall x :: x in s ==> x > 0;

+  requires |s| > 0 {

+    if * {

+      // Fails

+      assert s[0] > 0; // WISH

+    } else if * {

+      // Works

+      assert s[0] in s;

+      assert s[0] > 0;

+    }

+}

+

+method InSeqNoAutoTriggers(s: seq<int>, i: nat)

+  requires forall x {:autotriggers false} :: x in s ==> x > 0;

+  requires |s| > 0 {

+    assert s[0] > 0; // Works (Z3 matches on $Box above)

+}