protected override void ResolveTriggers(ResolutionContext rc)
{
//Contract.Requires(rc != null);
for (Trigger tr = this.Triggers; tr != null; tr = tr.Next)
{
int prevErrorCount = rc.ErrorCount;
tr.Resolve(rc);
if (prevErrorCount == rc.ErrorCount)
{
// for positive triggers, make sure all bound variables are mentioned
if (tr.Pos)
{
Set /*Variable*/ freeVars = new Set/*Variable*/ ();
tr.ComputeFreeVariables(freeVars);
foreach (Variable /*!*/ v in Dummies)
{
Contract.Assert(v != null);
if (!freeVars[v])
{
rc.Error(tr, "trigger must mention all quantified variables, but does not mention: {0}", v);
}
}
}
}
}
}
public override void Typecheck(TypecheckingContext tc)
{
//Contract.Requires(tc != null);
for (QKeyValue kv = this.Attributes; kv != null; kv = kv.Next)
{
kv.Typecheck(tc);
}
for (Trigger tr = this.Triggers; tr != null; tr = tr.Next)
{
tr.Typecheck(tc);
}
Body.Typecheck(tc);
Contract.Assert(Body.Type != null); // follows from postcondition of Expr.Typecheck
if (!Body.Type.Unify(Type.Bool))
{
tc.Error(this, "quantifier body must be of type bool");
}
this.Type = Type.Bool;
// Check that type parameters occur in the types of the
// dummies, or otherwise in the triggers. This can only be
// done after typechecking
List <TypeVariable> /*!*/
unmentionedParameters = GetUnmentionedTypeParameters();
Contract.Assert(unmentionedParameters != null);
if (unmentionedParameters.Count > 0)
{
// all the type parameters that do not occur in dummy types
// have to occur in triggers
for (Trigger tr = this.Triggers; tr != null; tr = tr.Next)
{
// for positive triggers, make sure all bound variables are mentioned
if (tr.Pos)
{
Set /*Variable*/
freeVars = new Set/*Variable*/ ();
tr.ComputeFreeVariables(freeVars);
foreach (TypeVariable /*!*/ v in unmentionedParameters)
{
Contract.Assert(v != null);
if (!freeVars[v])
{
tc.Error(tr,
"trigger does not mention {0}, which does not occur in variables types either",
v);
}
}
}
}
}
}
