private static bool ShallowEq(DatatypeValue expr1, DatatypeValue expr2)
{
return // Implied by Ctor equality: expr1.DatatypeName == expr2.DatatypeName &&
// Implied by Ctor equality: expr1.MemberName == expr2.MemberName &&
(expr1.Ctor == expr2.Ctor &&
// Contextual information: expr1.IsCoCall == expr2.IsCoCall &&
TriggerUtils.SameLists(expr1.InferredTypeArgs, expr2.InferredTypeArgs, TypeEq));
}
protected override void EmitDatatypeValue(DatatypeValue dtv, string dtName, string ctorName, string arguments, TargetWriter wr)
{
var dt = dtv.Ctor.EnclosingDatatype;
if (dt is TupleTypeDecl)
{
wr.Write("_dafny.Tuple.of({0})", arguments);
}
else
{
wr.Write("{0}.{1}.create_{2}({3})", dt.Module.CompileName, dtName, ctorName, arguments);
}
}
public Tuple<Method,TypeApply> GetSeqBuildMethod(Type t, SeqTree tree, List<bool> elemDimensions)
{
if (elemDimensions.Count == 0)
{
return GetSeqMethod(t, "seq_Empty");
}
if (elemDimensions.Count == 2 && elemDimensions[0] && elemDimensions[1])
{
return GetSeqMethod(t, "seq_Append");
}
string op = "seq_" + SeqTree.TreeName(tree);
DatatypeDecl seqDecl = FindDatatype("Seq");
var tok = new Bpl.Token(0, 0);
tok.filename = @"!\Seq.dfy";
TypeApply tApp = Compile_SeqType((SeqType)t);
Type dataType = new UserDefinedType(tok, "Seq", seqDecl, new List<Type> { ((SeqType)t).Arg });
Type elemType = ((SeqType)t).Arg;
Func<string,Type,Expression> idExpr = (x, typ) => {
var e = new IdentifierExpr(tok, x);
e.Type = typ;
e.Var = new LocalVariable(tok, tok, x, typ, false);
return e;
};
Func<string,List<Expression>,FunctionCallExpr> seqCall = (x, args) => {
var seqOp = GetSeqOperation(t, x);
FunctionCallExpr callExpr = new FunctionCallExpr(
tok, "Seq_Empty", new ThisExpr(tok), tok, args);
callExpr.Function = seqOp.Item1;
callExpr.TypeArgumentSubstitutions = seqOp.Item2.typeArgs;
return callExpr;
};
Expression empty = seqCall("Seq_Empty", new List<Expression> {});
int varCount = 0;
Func<SeqTree,Expression> resultRec = null;
resultRec = (subtree) =>
{
if (subtree == null)
{
return idExpr("s" + (varCount++), dataType);
}
if (subtree.buildCount >= 0)
{
Expression build = empty;
for (int i = 0; i < subtree.buildCount; i++)
{
build = seqCall("Seq_Build", new List<Expression>
{ build, idExpr("a" + (varCount++), elemType) });
}
return build;
}
else
{
return seqCall("Seq_Append", new List<Expression>
{ resultRec(subtree.left), resultRec(subtree.right) });
}
};
Expression result = resultRec(tree);
Expression post = seqCall("Seq_Equal", new List<Expression> { idExpr("s", dataType), result });
List<Statement> stmts = new List<Statement>();
for (int i = elemDimensions.Count; i > 0;)
{
bool isFirst = (i == elemDimensions.Count);
i--;
if (elemDimensions[i])
{
if (isFirst)
{
stmts.Add(new AssignStmt(tok, tok, idExpr("s", dataType),
new ExprRhs(idExpr("s" + i, dataType))));
}
else
{
// s := seq_Append(s9, s);
var selectExpr = new MemberSelectExpr(tok, new ThisExpr(tok), "seq_Append");
selectExpr.Member = FindMethod(selectExpr.MemberName); // Manually resolve here
selectExpr.TypeApplication = new List<Type>() { elemType }; // Manually resolve here
selectExpr.Type = new InferredTypeProxy(); // Manually resolve here
CallStmt callStmt = new CallStmt(tok, tok,
new List<Expression> {idExpr("s", dataType)},
selectExpr, new List<Expression>
{ idExpr("s" + i, dataType), idExpr("s", dataType) });
stmts.Add(callStmt);
}
}
else
{
if (isFirst)
{
DatatypeValue nil = new DatatypeValue(tok, "Seq", "Nil", new List<Expression>() {});
nil.Type = dataType;
nil.InferredTypeArgs = new List<Type> { elemType };
nil.Ctor = seqDecl.Ctors[0];
Util.Assert(nil.Ctor.Name == "Seq_Nil");
stmts.Add(new AssignStmt(tok, tok, idExpr("s", dataType), new ExprRhs(nil)));
}
// lemma_Seq_Cons(ai, s);
var selectExpr = new MemberSelectExpr(tok, new ThisExpr(tok), "lemma_Seq_Cons");
selectExpr.Member = FindMethod(selectExpr.MemberName); // Manually resolve here
selectExpr.TypeApplication = new List<Type>() { elemType }; // Manually resolve here
selectExpr.Type = new InferredTypeProxy(); // Manually resolve here
CallStmt callStmt = new CallStmt(tok, tok,
new List<Expression> {},
selectExpr, new List<Expression>
{ idExpr("a" + i, elemType), idExpr("s", dataType) });
callStmt.IsGhost = true;
stmts.Add(callStmt);
DatatypeValue cons = new DatatypeValue(tok, "Seq", "Cons", new List<Expression>()
{ idExpr("a" + i, elemType), idExpr("s", dataType) });
cons.Type = dataType;
cons.InferredTypeArgs = new List<Type> { elemType };
cons.Ctor = seqDecl.Ctors[1];
Util.Assert(cons.Ctor.Name == "Seq_Cons");
stmts.Add(new AssignStmt(tok, tok, idExpr("s", dataType), new ExprRhs(cons)));
}
}
BlockStmt body = new BlockStmt(tok, tok, stmts);
List<Formal> ins = new List<Formal>();
for (int i = 0; i < elemDimensions.Count; i++)
{
bool isSeq = elemDimensions[i];
ins.Add(new Formal(tok, (isSeq ? "s" : "a") + i, isSeq ? dataType : elemType, true, false));
}
List<Formal> outs = new List<Formal> { new Formal(tok, "s", dataType, false, false) };
List<MaybeFreeExpression> reqs = new List<MaybeFreeExpression>();
List<MaybeFreeExpression> enss = new List<MaybeFreeExpression> { new MaybeFreeExpression(post) };
Specification<FrameExpression> mods = new Specification<FrameExpression>(new List<FrameExpression>(), null);
Specification<Expression> decs = new Specification<Expression>(new List<Expression>(), null);
Attributes attrs = new Attributes("dafnycc_conservative_seq_triggers", new List<Expression>(), null);
Method m = new Method(tok, op, true, false, tApp.typeParams, ins, outs, reqs, mods, enss, decs, body, attrs, tok);
m.EnclosingClass = GetSeqMethod(t, "seq_Append").Item1.EnclosingClass;
return Tuple.Create(m, Compile_Method(m, tApp.typeArgs));
}
void ParensExpression(out Expression e, bool allowSemi, bool allowLambda)
{
IToken x;
var args = new List<Expression>();
Expect(50);
x = t;
if (StartOf(7)) {
Expressions(args);
}
Expect(51);
if (args.Count == 1) {
e = new ParensExpression(x, args[0]);
} else {
// make sure the corresponding tuple type exists
var tmp = theBuiltIns.TupleType(x, args.Count, true);
e = new DatatypeValue(x, BuiltIns.TupleTypeName(args.Count), BuiltIns.TupleTypeCtorName, args);
}
}
List <Expression> GenerateAutoReqs(Expression expr, Function parent)
{
List <Expression> reqs = new List <Expression>();
Func <Expression, List <Expression> > generateAutoReqs = e => GenerateAutoReqs(e, parent);
if (expr is LiteralExpr)
{
}
else if (expr is ThisExpr)
{
}
else if (expr is IdentifierExpr)
{
}
else if (expr is SeqDisplayExpr)
{
SeqDisplayExpr e = (SeqDisplayExpr)expr;
foreach (var elt in e.Elements)
{
reqs.AddRange(generateAutoReqs(elt));
}
}
else if (expr is FieldSelectExpr)
{
FieldSelectExpr e = (FieldSelectExpr)expr;
reqs.AddRange(generateAutoReqs(e.Obj));
}
else if (expr is SeqSelectExpr)
{
SeqSelectExpr e = (SeqSelectExpr)expr;
reqs.AddRange(generateAutoReqs(e.Seq));
if (e.E0 != null)
{
reqs.AddRange(generateAutoReqs(e.E0));
}
if (e.E1 != null)
{
reqs.AddRange(generateAutoReqs(e.E1));
}
}
else if (expr is SeqUpdateExpr)
{
SeqUpdateExpr e = (SeqUpdateExpr)expr;
reqs.AddRange(generateAutoReqs(e.Seq));
reqs.AddRange(generateAutoReqs(e.Index));
reqs.AddRange(generateAutoReqs(e.Value));
}
else if (expr is FunctionCallExpr)
{
FunctionCallExpr e = (FunctionCallExpr)expr;
foreach (var arg in e.Args)
{
reqs.AddRange(generateAutoReqs(arg));
}
if (parent == null || parent.Name != e.name)
{
ReqFunction(e.Function);
reqs.AddRange(GatherReqs(e.Function, e.Args));
}
}
else if (expr is DatatypeValue)
{
DatatypeValue dtv = (DatatypeValue)expr;
for (int i = 0; i < dtv.Arguments.Count; i++)
{
Expression arg = dtv.Arguments[i];
reqs.AddRange(generateAutoReqs(arg));
}
}
else if (expr is OldExpr)
{
}
else if (expr is MatchExpr)
{
MatchExpr e = (MatchExpr)expr;
reqs.AddRange(generateAutoReqs(e.Source));
List <MatchCaseExpr> newMatches = new List <MatchCaseExpr>();
foreach (MatchCaseExpr caseExpr in e.Cases)
{
MatchCaseExpr c = new MatchCaseExpr(caseExpr.name, caseExpr.Arguments, Andify(generateAutoReqs(caseExpr.Body)));
newMatches.Add(c);
}
reqs.Add(new MatchExpr(e.Source, newMatches));
}
else if (expr is FreshExpr)
{
}
else if (expr is UnaryExpr)
{
UnaryExpr e = (UnaryExpr)expr;
Expression arg = e.E;
reqs.AddRange(generateAutoReqs(arg));
}
else if (expr is BinaryExpr)
{
BinaryExpr e = (BinaryExpr)expr;
switch (e.Op)
{
case BinaryExpr.Opcode.Imp:
case BinaryExpr.Opcode.And:
reqs.AddRange(generateAutoReqs(e.E0));
foreach (var req in generateAutoReqs(e.E1))
{
reqs.Add(new BinaryExpr(Token.NoToken, BinaryExpr.Opcode.Imp, e.E0, req));
}
break;
case BinaryExpr.Opcode.Or:
reqs.AddRange(generateAutoReqs(e.E0));
foreach (var req in generateAutoReqs(e.E1))
{
reqs.Add(new BinaryExpr(Token.NoToken, BinaryExpr.Opcode.Imp,
new UnaryExpr(Token.NoToken, UnaryExpr.Opcode.Not, e.E0), req));
}
break;
default:
reqs.AddRange(generateAutoReqs(e.E0));
reqs.AddRange(generateAutoReqs(e.E1));
break;
}
}
else if (expr is LetExpr)
{
var e = (LetExpr)expr;
if (e.Exact)
{
foreach (var rhs in e.RHSs)
{
reqs.AddRange(generateAutoReqs(rhs));
}
var new_reqs = generateAutoReqs(e.Body);
if (new_reqs.Count > 0)
{
reqs.Add(new LetExpr(e.Exact, e.LHSs, e.RHSs, Andify(new_reqs)));
}
}
}
else if (expr is QuantifierExpr)
{
QuantifierExpr e = (QuantifierExpr)expr;
var auto_reqs = generateAutoReqs(e.Term);
if (auto_reqs.Count > 0)
{
Expression allReqsSatisfied = Andify(auto_reqs);
Expression allReqsSatisfiedAndTerm = new BinaryExpr(Token.NoToken, BinaryExpr.Opcode.And, allReqsSatisfied, e.Term);
e.Term = allReqsSatisfiedAndTerm;
}
}
else if (expr is StmtExpr)
{
var e = (StmtExpr)expr;
reqs.AddRange(generateAutoReqs(e.E));
}
else if (expr is ITEExpr)
{
ITEExpr e = (ITEExpr)expr;
reqs.AddRange(generateAutoReqs(e.Test));
reqs.Add(new ITEExpr(e.Test, Andify(generateAutoReqs(e.Thn)), Andify(generateAutoReqs(e.Els))));
}
return(reqs);
}
public RtlExp GhostExpressionRec(Expression exp, bool inRecSpec = false, bool inRequiresOrOld = false)
{
Util.Assert(!isPrinting);
exp = GetExp(exp);
StmtExpr stmtExpr = exp as StmtExpr;
IdentifierExpr idExp = exp as IdentifierExpr;
LiteralExpr literal = exp as LiteralExpr;
BinaryExpr binary = exp as BinaryExpr;
UnaryExpr unary = exp as UnaryExpr;
ITEExpr ite = exp as ITEExpr;
ExistsExpr existsExp = exp as ExistsExpr;
ForallExpr forallExp = exp as ForallExpr;
LetExpr letExp = exp as LetExpr;
MatchExpr matchExp = exp as MatchExpr;
OldExpr oldExp = exp as OldExpr;
FreshExpr freshExp = exp as FreshExpr;
FunctionCallExpr funCall = exp as FunctionCallExpr;
DatatypeValue dataVal = exp as DatatypeValue;
FieldSelectExpr fieldSelect = exp as FieldSelectExpr;
SeqSelectExpr seqSelect = exp as SeqSelectExpr;
SeqUpdateExpr seqUpdate = exp as SeqUpdateExpr;
SeqDisplayExpr seqDisplay = exp as SeqDisplayExpr;
Func <Expression, RtlExp> G = e => GhostExpression(e, inRecSpec, inRequiresOrOld);
if (stmtExpr != null)
{
if (stmtExprEnabled)
{
if (ignoreStmtExpr == 0)
{
AddGhostStatement(stmtExpr.S);
}
return(G(stmtExpr.E));
}
else
{
throw new Exception("not implemented: cannot handle statement expression here");
}
}
else if (idExp != null)
{
return(AsVar(idExp));
}
else if (literal != null && literal.Value is BigInteger)
{
return(new RtlInt((BigInteger)(literal.Value)));
}
else if (literal != null && literal.Value is bool)
{
return(new RtlLiteral((bool)(literal.Value) ? "true" : "false"));
}
else if (literal != null && literal.Value == null)
{
return(new RtlLiteral("ArrayOfInt(0 - 1, NO_ABS)"));
}
else if (literal != null && literal.Value is Microsoft.Basetypes.BigDec)
{
return(new RtlLiteral(((Microsoft.Basetypes.BigDec)literal.Value).ToDecimalString()));
}
else if (binary != null)
{
string op = null;
string internalOp = null;
CompileFunction compileFunction = this as CompileFunction;
string thisFuncName = (compileFunction == null) ? null : compileFunction.function.Name;
switch (binary.ResolvedOp)
{
case BinaryExpr.ResolvedOpcode.SeqEq:
return(new RtlApply(dafnySpec.GetSeqOperationName(AppType(binary.E0.Type), "Seq_Equal"),
new RtlExp[] { G(binary.E0), G(binary.E1) }));
case BinaryExpr.ResolvedOpcode.SeqNeq:
return(new RtlLiteral("(!" +
new RtlApply(dafnySpec.GetSeqOperationName(AppType(binary.E0.Type), "Seq_Equal"),
new RtlExp[] { G(binary.E0), G(binary.E1) }) + ")"));
case BinaryExpr.ResolvedOpcode.Concat:
return(new RtlApply(dafnySpec.GetSeqOperationName(AppType(binary.Type), "Seq_Append"),
new RtlExp[] { G(binary.E0), G(binary.E1) }));
}
if (binary.Op == BinaryExpr.Opcode.Exp)
{
binary = new BinaryExpr(binary.tok, BinaryExpr.Opcode.Imp, binary.E0, binary.E1);
}
switch (binary.Op)
{
case BinaryExpr.Opcode.Disjoint:
case BinaryExpr.Opcode.In:
case BinaryExpr.Opcode.NotIn:
throw new Exception("not implemented: binary operator '" + BinaryExpr.OpcodeString(binary.Op) + "'");
}
if (AppType(binary.E0.Type) is IntType && AppType(binary.E1.Type) is IntType)
{
switch (binary.Op)
{
case BinaryExpr.Opcode.Le: internalOp = "INTERNAL_le_boogie"; break;
case BinaryExpr.Opcode.Lt: internalOp = "INTERNAL_lt_boogie"; break;
case BinaryExpr.Opcode.Ge: internalOp = "INTERNAL_ge_boogie"; break;
case BinaryExpr.Opcode.Gt: internalOp = "INTERNAL_gt_boogie"; break;
case BinaryExpr.Opcode.Add: internalOp = "INTERNAL_add_boogie"; break;
case BinaryExpr.Opcode.Sub: internalOp = "INTERNAL_sub_boogie"; break;
case BinaryExpr.Opcode.Mul:
op = "*";
if (thisFuncName != "INTERNAL_mul")
{
internalOp = FunName("INTERNAL__mul");
}
break;
case BinaryExpr.Opcode.Div:
op = "div";
if (thisFuncName != "INTERNAL_div")
{
internalOp = FunName("INTERNAL__div");
}
break;
case BinaryExpr.Opcode.Mod:
op = "mod";
if (thisFuncName != "INTERNAL_mod")
{
internalOp = FunName("INTERNAL__mod");
}
break;
default:
op = BinaryExpr.OpcodeString(binary.Op);
break;
}
}
else
{
op = BinaryExpr.OpcodeString(binary.Op);
}
if (internalOp == null)
{
return(new RtlBinary(op, G(binary.E0), G(binary.E1)));
}
else
{
return(new RtlApply(internalOp, new RtlExp[]
{ G(binary.E0), G(binary.E1) }));
}
}
else if (unary != null && unary.Op == UnaryExpr.Opcode.Not)
{
return(new RtlLiteral("(!(" + G(unary.E) + "))"));
}
else if (unary != null && unary.Op == UnaryExpr.Opcode.SeqLength)
{
return(new RtlApply(dafnySpec.GetSeqOperationName(AppType(unary.E.Type), "Seq_Length"),
new RtlExp[] { G(unary.E) }));
}
else if (ite != null)
{
return(GhostIfThenElse(G(ite.Test), () => G(ite.Thn), () => G(ite.Els)));
}
else if (funCall != null)
{
switch (funCall.Function.Name)
{
case "left":
case "right":
case "relation":
case "public":
Util.Assert(funCall.Args.Count == 1);
return(new RtlApply(funCall.Function.Name, new RtlExp[] { G(funCall.Args[0]) }));
case "sizeof":
Util.Assert(funCall.Args.Count == 1);
return(new RtlApply(funCall.Function.Name + "##" + TypeString(AppType(funCall.Args[0].Type)),
new RtlExp[] { G(funCall.Args[0]) }));
case "INTERNAL_add_raw":
Util.Assert(funCall.Args.Count == 2);
return(new RtlBinary("+", G(funCall.Args[0]), G(funCall.Args[1])));
case "INTERNAL_sub_raw":
Util.Assert(funCall.Args.Count == 2);
return(new RtlBinary("-", G(funCall.Args[0]), G(funCall.Args[1])));
case "IntToReal":
Util.Assert(funCall.Args.Count == 1);
return(new RtlApply("real", new RtlExp[] { G(funCall.Args[0]) }));
case "RealToInt":
Util.Assert(funCall.Args.Count == 1);
return(new RtlApply("int", new RtlExp[] { G(funCall.Args[0]) }));
}
TypeApply app = dafnySpec.Compile_Function(funCall.Function,
funCall.TypeArgumentSubstitutions.ToDictionary(p => p.Key, p => AppType(p.Value)));
string name = FunName(SimpleName(app.AppName()));
string fullName = FunName(SimpleName(app.AppFullName()));
List <RtlExp> rtlArgs = funCall.Args.Select(G).ToList();
List <RtlExp> rtlReads = funCall.Function.Reads.Where(e => e.Field != null).ToList()
.ConvertAll(e => (RtlExp) new RtlVar(
GhostVar(e.FieldName), e.Field.IsGhost, AppType(e.Field.Type)));
rtlArgs = rtlReads.Concat(rtlArgs).ToList();
if (name.EndsWith("__INTERNAL__HEAP"))
{
name = name.Substring(0, name.Length - "__INTERNAL__HEAP".Length);
}
else if (DafnySpec.IsHeapFunction(funCall.Function))
{
rtlArgs.Insert(0, new RtlLiteral(inRequiresOrOld ? "$absMem_old" : "$absMem"));
}
if (Attributes.Contains(funCall.Function.Attributes, "opaque") &&
funCall.Function.Formals.Count + rtlReads.Count == 0)
{
rtlArgs.Insert(0, new RtlLiteral("true"));
}
if (fullName == recFunName)
{
name = fullName;
}
if (name == recFunName)
{
recCalls.Add(new List <RtlExp>(rtlArgs));
rtlArgs.Insert(0, new RtlApply("decreases_" + name, new List <RtlExp>(rtlArgs)));
rtlArgs.Insert(1, new RtlLiteral(inRecSpec ? "__unroll" : "__unroll + 1"));
name = "rec_" + name;
}
return(new RtlApply(name, rtlArgs));
}
else if (dataVal != null)
{
bool isSeq = dataVal.Type.TypeName(null).StartsWith("Seq<");
return(new RtlApply((isSeq ? "_" : "") + dafnySpec.Compile_Constructor(
dataVal.Type, dataVal.Ctor.Name, dataVal.InferredTypeArgs, typeApply.typeArgs).AppName(),
dataVal.Arguments.Select(G)));
}
else if (existsExp != null || forallExp != null)
{
QuantifierExpr qExp = (QuantifierExpr)exp;
bool isForall = forallExp != null;
var varTuples = qExp.BoundVars.Select(v => Tuple.Create(GhostVar(v.Name), v.IsGhost, v.Type));
var oldRenamer = PushRename(qExp.BoundVars.Select(v => v.Name));
var oldStmtExprEnabled = stmtExprEnabled;
stmtExprEnabled = false;
RtlExp rExp = new RtlLiteral((isForall ? "(forall " : "(exists ")
+ string.Join(", ", qExp.BoundVars.Select(v => GhostVar(v.Name) + ":" + TypeString(AppType(v.Type))))
+ " :: " + Triggers(qExp.Attributes, G) + " "
+ GetTypeWellFormedExp(varTuples.ToList(), isForall ? "==>" : "&&", G(qExp.Term)) + ")");
stmtExprEnabled = oldStmtExprEnabled;
PopRename(oldRenamer);
return(rExp);
}
else if (letExp != null)
{
List <RtlExp> rhss;
if (letExp.Exact)
{
rhss = letExp.RHSs.ConvertAll(e => G(e));
}
else if (letExp.LHSs.Count == 1 && LiteralExpr.IsTrue(letExp.RHSs[0]) && AppType(letExp.LHSs[0].Var.Type) is IntType)
{
rhss = new List <RtlExp> {
new RtlLiteral("0")
};
}
else
{
throw new Exception("not implemented: LetExpr: " + letExp);
}
return(GhostLet(exp.tok, letExp.LHSs.ConvertAll(lhs => lhs.Var), rhss, () => G(letExp.Body)));
}
else if (matchExp != null)
{
if (matchExp.MissingCases.Count != 0)
{
throw new Exception("not implemented: MatchExpr with missing cases: " + matchExp);
}
//- match src case c1(ps1) => e1 ... cn(psn) => en
//- -->
//- let x := src in
//- if x is c1 then let ps1 := ...x.f1... in e1 else
//- if x is c2 then let ps2 := ...x.f2... in e2 else
//- let ps3 := ...x.f3... in e3
var src = G(matchExp.Source);
var cases = matchExp.Cases;
string x = TempName();
Func <RtlExp> body = null;
for (int i = cases.Count; i > 0;)
{
i--;
MatchCaseExpr c = cases[i];
Func <List <RtlExp> > cRhss = () => c.Ctor.Formals.ConvertAll(f => (RtlExp) new RtlLiteral("("
+ f.Name + "#" + c.Ctor.Name + "(" + GhostVar(x) + "))"));
Func <RtlExp> ec = () => GhostLet(exp.tok, c.Arguments, cRhss(), () => G(c.Body));
if (body == null)
{
body = ec;
}
else
{
var prevBody = body;
body = () => GhostIfThenElse(new RtlLiteral("(" + GhostVar(x) + " is " + c.Ctor.Name + ")"),
ec, prevBody);
}
}
return(GhostLet(exp.tok, new List <BoundVar> {
new BoundVar(exp.tok, x, matchExp.Source.Type)
},
new List <RtlExp> {
src
}, body));
}
else if (oldExp != null)
{
return(new RtlLiteral("old(" + GhostExpression(oldExp.E, inRecSpec, true) + ")"));
}
else if (freshExp != null)
{
Util.Assert(DafnySpec.IsArrayType(freshExp.E.Type));
string abs = G(freshExp.E) + ".arrAbs";
return(new RtlLiteral("(heap_old.absData[" + abs + "] is AbsNone)"));
}
else if (fieldSelect != null && fieldSelect.FieldName.EndsWith("?"))
{
string constructor = fieldSelect.FieldName.Substring(0, fieldSelect.FieldName.Length - 1);
constructor = dafnySpec.Compile_Constructor(fieldSelect.Obj.Type, constructor, null, typeApply.typeArgs).AppName();
bool isSeq = fieldSelect.Obj.Type.TypeName(null).StartsWith("Seq<");
return(isSeq
? new RtlLiteral("is_" + constructor + "(" + G(fieldSelect.Obj) + ")")
: new RtlLiteral("((" + G(fieldSelect.Obj) + ") is " + constructor + ")"));
}
else if (fieldSelect != null && !fieldSelect.Field.IsStatic && AppType(fieldSelect.Obj.Type) is UserDefinedType &&
fieldSelect.Field is DatatypeDestructor)
{
DatatypeDestructor field = (DatatypeDestructor)fieldSelect.Field;
string constructor = dafnySpec.Compile_Constructor(fieldSelect.Obj.Type,
field.EnclosingCtor.Name, null, typeApply.typeArgs).AppName();
bool isSeq = fieldSelect.Obj.Type.TypeName(null).StartsWith("Seq<");
return(new RtlLiteral("(" + fieldSelect.FieldName + (isSeq ? "_" : "#") + constructor
+ "(" + G(fieldSelect.Obj) + "))"));
}
else if (fieldSelect != null && DafnySpec.IsArrayType(AppType(fieldSelect.Obj.Type)) &&
fieldSelect.FieldName == "Length")
{
return(new RtlLiteral("(Arr_Length(" + G(fieldSelect.Obj) + "))"));
}
else if (fieldSelect != null && fieldSelect.Obj is ImplicitThisExpr)
{
//- we don't support objects yet, so interpret this as a global variable
return(new RtlVar(GhostVar(fieldSelect.FieldName), true, fieldSelect.Type));
}
else if (seqSelect != null)
{
if (seqSelect.SelectOne && DafnySpec.IsArrayType(AppType(seqSelect.Seq.Type)))
{
return(new RtlExpComputed(e => "fun_INTERNAL__array__elems__index("
+ (inRequiresOrOld ? "$absMem_old" : "$absMem") + "[" + e.args[0] + ".arrAbs], ("
+ e.args[1] + "))", new RtlExp[] { G(seqSelect.Seq), G(seqSelect.E0) }));
}
else if (seqSelect.SelectOne)
{
return(new RtlApply(dafnySpec.GetSeqOperationName(AppType(seqSelect.Seq.Type), "Seq_Index"),
new RtlExp[] { G(seqSelect.Seq), G(seqSelect.E0) }));
}
else
{
RtlExp seq = G(seqSelect.Seq);
if (DafnySpec.IsArrayType(AppType(seqSelect.Seq.Type)))
{
seq = new RtlApply(FunName("Seq__FromArray"), new RtlExp[] {
new RtlLiteral(inRequiresOrOld ? "$absMem_old" : "$absMem"), seq
});
}
if (seqSelect.E1 != null)
{
seq = new RtlApply(dafnySpec.GetSeqOperationName(AppType(seqSelect.Type), "Seq_Take"),
new RtlExp[] { seq, G(seqSelect.E1) });
}
if (seqSelect.E0 != null)
{
seq = new RtlApply(dafnySpec.GetSeqOperationName(AppType(seqSelect.Type), "Seq_Drop"),
new RtlExp[] { seq, G(seqSelect.E0) });
}
return(seq);
}
}
else if (seqUpdate != null)
{
if (seqUpdate.ResolvedUpdateExpr != null)
{
return(GhostExpressionRec(seqUpdate.ResolvedUpdateExpr, inRecSpec, inRequiresOrOld));
}
return(new RtlApply(dafnySpec.GetSeqOperationName(AppType(seqUpdate.Seq.Type), "Seq_Update"),
new RtlExp[] { G(seqUpdate.Seq), G(seqUpdate.Index), G(seqUpdate.Value) }));
}
else if (seqDisplay != null)
{
RtlExp seq = new RtlApply(dafnySpec.GetSeqOperationName(AppType(seqDisplay.Type), "Seq_Empty"), new RtlExp[0]);
foreach (Expression ei in seqDisplay.Elements)
{
seq = new RtlApply(dafnySpec.GetSeqOperationName(AppType(seqDisplay.Type), "Seq_Build"),
new RtlExp[] { seq, G(ei) });
}
return(seq);
}
else
{
throw new Exception("not implemented: " + exp);
}
}
