/// <summary>
/// Checks whether the assertions in the context are consistent or not.
/// </summary>
public static Status Check(Context ctx, List<BoolExpr> core, ref Model model, ref Expr proof, params Expr[] assumptions)
{
Z3_lbool r;
model = null;
proof = null;
if (assumptions == null || assumptions.Length == 0)
r = (Z3_lbool)Native.Z3_check(ctx.nCtx);
else {
IntPtr mdl = IntPtr.Zero, prf = IntPtr.Zero;
uint core_size = 0;
IntPtr[] native_core = new IntPtr[assumptions.Length];
r = (Z3_lbool)Native.Z3_check_assumptions(ctx.nCtx,
(uint)assumptions.Length, AST.ArrayToNative(assumptions),
ref mdl, ref prf, ref core_size, native_core);
for (uint i = 0; i < core_size; i++)
core.Add((BoolExpr)Expr.Create(ctx, native_core[i]));
if (mdl != IntPtr.Zero) {
model = new Model(ctx, mdl);
}
if (prf != IntPtr.Zero) {
proof = Expr.Create(ctx, prf);
}
}
switch (r)
{
case Z3_lbool.Z3_L_TRUE: return Status.SATISFIABLE;
case Z3_lbool.Z3_L_FALSE: return Status.UNSATISFIABLE;
default: return Status.UNKNOWN;
}
}
internal AcceptorBase(FuncDecl symbol, Expr guard, ExprSet[] lookahead)
{
this.symbol = symbol;
this.guard = guard;
this.lookahead = lookahead;
this.lhs = new Pair<FuncDecl, Sequence<ExprSet>>(symbol, new Sequence<ExprSet>(lookahead));
}
//bool CSmode = false;
/// <summary>
/// Returns a pretty printed view of the given term.
/// </summary>
/// <param name="term">the given term</param>
/// <param name="lookupVarName">lookup function for variable names</param>
public string DescribeExpr(Expr term, Func<Expr, string> lookupVarName)
{
__lookupVarName = lookupVarName;
var str = DescribeExpr(term);
__lookupVarName = null;
return str;
}
/// <summary>
/// Retrieves the interpretation (the assignment) of <paramref name="a"/> in the model.
/// </summary>
/// <param name="a">A Constant</param>
/// <returns>An expression if the constant has an interpretation in the model, null otherwise.</returns>
public Expr ConstInterp(Expr a)
{
Contract.Requires(a != null);
Context.CheckContextMatch(a);
return ConstInterp(a.FuncDecl);
}
public Automaton<Expr> getAutomata(Z3Provider z3p, Expr universe, Expr var, Sort sort)
{ //Sort for pairs (input theory, BV)
var bv = z3p.Z3.MkBitVecSort(BVConst.BVSIZE);
var pairSort = z3p.MkTupleSort(sort, bv);
var dfapair = this.Normalize().PushQuantifiers().getAutomata(z3p, new List<string>(), universe, var, sort);
//Compute the new moves by dropping the last bit of every element in the phiMoves
var newMoves = Automaton<Expr>.Empty.GetMoves().ToList();
foreach (var oldMove in dfapair.GetMoves())
{
var oldCond = oldMove.Label;
//Compute the new condition as ()
Expr newCond = oldCond;
//Update the new set of moves
newMoves.Add(new Move<Expr>(oldMove.SourceState, oldMove.TargetState, newCond));
}
//Build the new dfa with the new moves
var automaton = Automaton<Expr>.Create(dfapair.InitialState, dfapair.GetFinalStates(), newMoves);
return automaton.Determinize(z3p).Minimize(z3p);
}
internal Quantifier(Context ctx, bool isForall, Expr[] bound, Expr body, uint weight = 1, Pattern[] patterns = null, Expr[] noPatterns = null, Symbol quantifierID = null, Symbol skolemID = null)
: base(ctx)
{
Contract.Requires(ctx != null);
Contract.Requires(body != null);
Contract.Requires(patterns == null || Contract.ForAll(patterns, p => p != null));
Contract.Requires(noPatterns == null || Contract.ForAll(noPatterns, np => np != null));
Contract.Requires(bound == null || Contract.ForAll(bound, n => n != null));
Context.CheckContextMatch(noPatterns);
Context.CheckContextMatch(patterns);
//Context.CheckContextMatch(bound);
Context.CheckContextMatch(body);
if (noPatterns == null && quantifierID == null && skolemID == null)
{
NativeObject = Native.Z3_mk_quantifier_const(ctx.nCtx, (isForall) ? 1 : 0, weight,
AST.ArrayLength(bound), AST.ArrayToNative(bound),
AST.ArrayLength(patterns), AST.ArrayToNative(patterns),
body.NativeObject);
}
else
{
NativeObject = Native.Z3_mk_quantifier_const_ex(ctx.nCtx, (isForall) ? 1 : 0, weight,
AST.GetNativeObject(quantifierID), AST.GetNativeObject(skolemID),
AST.ArrayLength(bound), AST.ArrayToNative(bound),
AST.ArrayLength(patterns), AST.ArrayToNative(patterns),
AST.ArrayLength(noPatterns), AST.ArrayToNative(noPatterns),
body.NativeObject);
}
}
/// <summary>
/// Z3 expr to C# pretty printer
/// </summary>
public CSPrettyPrinter(Context z3)
{
this.charSort = z3.MkBitVecSort(16);
this.tt = z3.MkBool(true);
this.ff = z3.MkBool(false);
this.encoding = 16;
}
internal AcceptorBase(FuncDecl symbol, Expr guard, int rank)
{
this.symbol = symbol;
this.guard = guard;
ExprSet[] ts = new ExprSet[rank];
for (int i = 0; i < rank; i++)
ts[i] = new ExprSet();
lookahead = ts;
}
/// <summary>
/// Returns a pretty printed view of the given term. Uses C# compliant expression notation.
/// </summary>
/// <param name="term">the given term</param>
/// <param name="lookupVarName">lookup function for variable names</param>
public string DescribeExprCS(Expr term, Func<Expr, string> lookupVarName)
{
//CSmode = true;
__lookupVarName = lookupVarName;
var str = DescribeExpr(term);
__lookupVarName = null;
//CSmode = false;
return str;
}
/// <summary>
/// Create axiom: function f is injective in the i-th argument.
/// </summary>
/// <remarks>
/// The following axiom is produced:
/// <c>
/// forall (x_0, ..., x_n) finv(f(x_0, ..., x_i, ..., x_{n-1})) = x_i
/// </c>
/// Where, <code>finv</code>is a fresh function declaration.
/// </summary>
public static BoolExpr InjAxiom(Context ctx, FuncDecl f, int i)
{
Sort[] domain = f.Domain;
uint sz = f.DomainSize;
if (i >= sz)
{
Console.WriteLine("failed to create inj axiom");
return null;
}
/* declare the i-th inverse of f: finv */
Sort finv_domain = f.Range;
Sort finv_range = domain[i];
FuncDecl finv = ctx.MkFuncDecl("f_fresh", finv_domain, finv_range);
/* allocate temporary arrays */
Expr[] xs = new Expr[sz];
Symbol[] names = new Symbol[sz];
Sort[] types = new Sort[sz];
/* fill types, names and xs */
for (uint j = 0; j < sz; j++)
{
types[j] = domain[j];
names[j] = ctx.MkSymbol(String.Format("x_{0}", j));
xs[j] = ctx.MkBound(j, types[j]);
}
Expr x_i = xs[i];
/* create f(x_0, ..., x_i, ..., x_{n-1}) */
Expr fxs = f[xs];
/* create f_inv(f(x_0, ..., x_i, ..., x_{n-1})) */
Expr finv_fxs = finv[fxs];
/* create finv(f(x_0, ..., x_i, ..., x_{n-1})) = x_i */
Expr eq = ctx.MkEq(finv_fxs, x_i);
/* use f(x_0, ..., x_i, ..., x_{n-1}) as the pattern for the quantifier */
Pattern p = ctx.MkPattern(new Expr[] { fxs });
/* create & assert quantifier */
BoolExpr q = ctx.MkForall(
types, /* types of quantified variables */
names, /* names of quantified variables */
eq,
1,
new Pattern[] { p } /* patterns */);
return q;
}
/// <summary>
/// Computes an interpolant.
/// </summary>
/// <remarks>For more information on interpolation please refer
/// too the function Z3_get_interpolant in the C/C++ API, which is
/// well documented.</remarks>
public BoolExpr[] GetInterpolant(Expr pf, Expr pat, Params p)
{
Contract.Requires(pf != null);
Contract.Requires(pat != null);
Contract.Requires(p != null);
Contract.Ensures(Contract.Result<Expr>() != null);
CheckContextMatch(pf);
CheckContextMatch(pat);
CheckContextMatch(p);
ASTVector seq = new ASTVector(this, Native.Z3_get_interpolant(nCtx, pf.NativeObject, pat.NativeObject, p.NativeObject));
return seq.ToBoolExprArray();
}
/// <summary>
/// Computes an interpolant.
/// </summary>
/// <remarks>For more information on interpolation please refer
/// too the function Z3_compute_interpolant in the C/C++ API, which is
/// well documented.</remarks>
public Z3_lbool ComputeInterpolant(Expr pat, Params p, out BoolExpr[] interp, out Model model)
{
Contract.Requires(pat != null);
Contract.Requires(p != null);
Contract.Ensures(Contract.ValueAtReturn(out interp) != null);
Contract.Ensures(Contract.ValueAtReturn(out model) != null);
CheckContextMatch(pat);
CheckContextMatch(p);
IntPtr i = IntPtr.Zero, m = IntPtr.Zero;
int r = Native.Z3_compute_interpolant(nCtx, pat.NativeObject, p.NativeObject, ref i, ref m);
interp = new ASTVector(this, i).ToBoolExprArray();
model = new Model(this, m);
return (Z3_lbool)r;
}
/// <summary>
/// Checks the correctness of an interpolant.
/// </summary>
/// <remarks>For more information on interpolation please refer
/// too the function Z3_check_interpolant in the C/C++ API, which is
/// well documented.</remarks>
public int CheckInterpolant(Expr[] cnsts, uint[] parents, BoolExpr[] interps, out string error, Expr[] theory)
{
Contract.Requires(cnsts.Length == parents.Length);
Contract.Requires(cnsts.Length == interps.Length + 1);
IntPtr n_err_str;
int r = Native.Z3_check_interpolant(nCtx,
(uint)cnsts.Length,
Expr.ArrayToNative(cnsts),
parents,
Expr.ArrayToNative(interps),
out n_err_str,
(uint)theory.Length,
Expr.ArrayToNative(theory));
error = Marshal.PtrToStringAnsi(n_err_str);
return r;
}
internal Quantifier(Context ctx, bool isForall, Sort[] sorts, Symbol[] names, Expr body,
uint weight = 1, Pattern[] patterns = null, Expr[] noPatterns = null,
Symbol quantifierID = null, Symbol skolemID = null
)
: base(ctx)
{
Contract.Requires(ctx != null);
Contract.Requires(sorts != null);
Contract.Requires(names != null);
Contract.Requires(body != null);
Contract.Requires(sorts.Length == names.Length);
Contract.Requires(Contract.ForAll(sorts, s => s != null));
Contract.Requires(Contract.ForAll(names, n => n != null));
Contract.Requires(patterns == null || Contract.ForAll(patterns, p => p != null));
Contract.Requires(noPatterns == null || Contract.ForAll(noPatterns, np => np != null));
Context.CheckContextMatch(patterns);
Context.CheckContextMatch(noPatterns);
Context.CheckContextMatch(sorts);
Context.CheckContextMatch(names);
Context.CheckContextMatch(body);
if (sorts.Length != names.Length)
throw new Z3Exception("Number of sorts does not match number of names");
IntPtr[] _patterns = AST.ArrayToNative(patterns);
if (noPatterns == null && quantifierID == null && skolemID == null)
{
NativeObject = Native.Z3_mk_quantifier(ctx.nCtx, (isForall) ? 1 : 0, weight,
AST.ArrayLength(patterns), AST.ArrayToNative(patterns),
AST.ArrayLength(sorts), AST.ArrayToNative(sorts),
Symbol.ArrayToNative(names),
body.NativeObject);
}
else
{
NativeObject = Native.Z3_mk_quantifier_ex(ctx.nCtx, (isForall) ? 1 : 0, weight,
AST.GetNativeObject(quantifierID), AST.GetNativeObject(skolemID),
AST.ArrayLength(patterns), AST.ArrayToNative(patterns),
AST.ArrayLength(noPatterns), AST.ArrayToNative(noPatterns),
AST.ArrayLength(sorts), AST.ArrayToNative(sorts),
Symbol.ArrayToNative(names),
body.NativeObject);
}
}
/// <summary>
/// Computes an interpolant.
/// </summary>
/// <remarks>For more information on interpolation please refer
/// too the function Z3_get_interpolant in the C/C++ API, which is
/// well documented.</remarks>
Expr[] GetInterpolant(Expr pf, Expr pat, Params p)
{
Contract.Requires(pf != null);
Contract.Requires(pat != null);
Contract.Requires(p != null);
Contract.Ensures(Contract.Result<Expr>() != null);
CheckContextMatch(pf);
CheckContextMatch(pat);
CheckContextMatch(p);
ASTVector seq = new ASTVector(this, Native.Z3_get_interpolant(nCtx, pf.NativeObject, pat.NativeObject, p.NativeObject));
uint n = seq.Size;
Expr[] res = new Expr[n];
for (uint i = 0; i < n; i++)
res[i] = Expr.Create(this, seq[i].NativeObject);
return res;
}
internal RankedAlphabet(
TreeTheory tt,
string[] symbols,
Dictionary<string, int> idMap,
Sort alphabetSort,
Sort nodeSort,
int[] ranks,
FuncDecl[] constructors,
FuncDecl[][] accessors,
FuncDecl[] testers,
FuncDecl acceptor,
Expr[] vars
)
{
this.tt = tt;
this.symbols = new List<string>(symbols).AsReadOnly();
this.idMap = idMap;
this.alphabetSort = alphabetSort;
this.nodeSort = nodeSort;
this.ranks = ranks;
this.constructors = constructors;
this.accessors = accessors;
this.testers = testers;
this.acceptor = acceptor;
this.vars = vars;
this.trans = tt.GetTrans(alphabetSort, alphabetSort);
this.emptyAcceptor = TreeTransducer.MkEmpty(this);
this.fullAcceptor = TreeTransducer.MkFull(this);
this.idAut = TreeTransducer.MkId(this);
this.symbolsOfRank = new Dictionary<int, List<FuncDecl>>();
for (int i = 0; i < ranks.Length; i++)
{
var r = ranks[i];
if (!symbolsOfRank.ContainsKey(r))
symbolsOfRank[r] = new List<FuncDecl>();
symbolsOfRank[r].Add(constructors[i]);
}
var attrDomain = tt.Z.MkFreshFuncDecl("_", new Sort[] { nodeSort }, tt.Z.BoolSort);
this.attrExpr = tt.Z.MkApp(attrDomain, vars[0]);
tt.Z.AssertAxiom(this.attrExpr, tt.Z.True, vars[0]);
}
public uint GetNumeralUInt(Expr t)
{
var ts = t.Sort;
if (t is IntNum)
return ((IntNum)t).UInt;
if (t is BitVecNum)
return ((BitVecNum)t).UInt;
//avoiding z3 bug: (GetSort(t) is TupleSort) == false even when t is a tuple
if ((t.Sort.Name.ToString().StartsWith("$")) && (GetTupleLength(t.Sort) == 1))
{
var v = t.Args[0];
if (v is IntNum)
return ((IntNum)v).UInt;
if (v is BitVecNum)
return ((BitVecNum)v).UInt;
throw new Exception();
}
throw new Exception();
}
public UnrankedTreeInfo(Sort treeListSort, FuncDecl getNodeValue, FuncDecl getSubtrees, FuncDecl mkNode,
FuncDecl mkLeaf, FuncDecl getLeafValue, FuncDecl isNode, FuncDecl isLeaf,
Expr empty, FuncDecl first, FuncDecl rest,
FuncDecl cons, FuncDecl isEmpty, FuncDecl isCons)
{
this.TreeListSort = treeListSort;
this.GetNodeLabel = getNodeValue;
this.GetNodeSubtrees = getSubtrees;
this.MkNode = mkNode;
this.EmptyTreeList = empty;
this.GetFirst = first;
this.GetRest = rest;
this.MkCons = cons;
this.IsEmpty = isEmpty;
this.IsCons = isCons;
this.MkLeaf = mkLeaf;
this.GetLeafValue = getLeafValue;
this.IsNode = isNode;
this.IsLeaf = isLeaf;
}
public Const(ConstDef def, FastTransducerInstance fti, Z3Provider z3p)
{
this.z3p = z3p;
this.name = def.id.text;
switch (def.sort.kind)
{
case (FastSortKind.Real):
{
sort = z3p.RealSort;
break;
}
case (FastSortKind.Bool):
{
sort = z3p.BoolSort;
break;
}
case (FastSortKind.Int):
{
sort = z3p.IntSort;
break;
}
case (FastSortKind.String):
{
sort = z3p.MkListSort(z3p.CharSort);
break;
}
case (FastSortKind.Tree):
{
foreach (var enumSort in fti.enums)
{
if (enumSort.name == def.sort.name.text)
{
sort = enumSort.sort;
break;
}
}
break;
}
}
this.value = GenerateZ3ExprFromExpr(def.expr, fti).Simplify();
}
internal override Automaton<Expr> getAutomata(Z3Provider z3p, List<string> variables, Expr universe, Expr var, Sort sort)
{
//var bit1 = z3p.Z3.MkInt2Bv(1,
// z3p.MkInt(1));
var bit1 = z3p.Z3.MkInt2BV(BVConst.BVSIZE, (IntExpr)z3p.MkInt(1));
//Sort for pairs (input theory, BV)
var bv = z3p.Z3.MkBitVecSort(BVConst.BVSIZE);
var pairSort = z3p.MkTupleSort(sort, bv);
//Add the representation of the existential variable to the list of variables
var newVariables = variables.ToArray().ToList();
newVariables.Insert(0, variable);
//Compute the DFA for the formula phi
var phiDfa = phi.getAutomata(z3p, newVariables, universe, var, sort);
//Compute the new moves by dropping the last bit of every element in the phiMoves
var newMoves = Automaton<Expr>.Empty.GetMoves().ToList();
foreach (var oldMove in phiDfa.GetMoves())
{
var oldCond = oldMove.Label;
var t = z3p.MkProj(1,var);
//Compute the new conditions
var newCond0 = z3p.ApplySubstitution(oldCond, t,
z3p.Z3.MkBVSHL((BitVecExpr)t, (BitVecExpr)bit1));
var newCond1 = z3p.ApplySubstitution(oldCond, t,
z3p.MkBvAdd(
z3p.Z3.MkBVSHL((BitVecExpr)t, (BitVecExpr)bit1),
bit1));
//Update the new set of moves
newMoves.Add(new Move<Expr>(oldMove.SourceState, oldMove.TargetState, z3p.MkOr(z3p.Simplify(newCond0),z3p.Simplify(newCond1))));
}
//Build the new dfa with the new moves
return Automaton<Expr>.Create(phiDfa.InitialState, phiDfa.GetFinalStates(), newMoves);
//.Determinize(z3p).MinimizeClassical(z3p, int.MaxValue,false);
}
/// <summary>
/// The finite set of distinct values that represent the interpretation for sort <paramref name="s"/>.
/// </summary>
/// <seealso cref="Sorts"/>
/// <param name="s">An uninterpreted sort</param>
/// <returns>An array of expressions, where each is an element of the universe of <paramref name="s"/></returns>
public Expr[] SortUniverse(Sort s)
{
Contract.Requires(s != null);
Contract.Ensures(Contract.Result<Expr[]>() != null);
ASTVector nUniv = new ASTVector(Context, Native.Z3_model_get_sort_universe(Context.nCtx, NativeObject, s.NativeObject));
uint n = nUniv.Size;
Expr[] res = new Expr[n];
for (uint i = 0; i < n; i++)
res[i] = Expr.Create(Context, nUniv[i].NativeObject);
return res;
}
/// <summary>
/// Alias for <c>Eval</c>.
/// </summary>
public Expr Evaluate(Expr t, bool completion = false)
{
Contract.Requires(t != null);
Contract.Ensures(Contract.Result<Expr>() != null);
return Eval(t, completion);
}
/// <summary>
/// Evaluates the expression <paramref name="t"/> in the current model.
/// </summary>
/// <remarks>
/// This function may fail if <paramref name="t"/> contains quantifiers,
/// is partial (MODEL_PARTIAL enabled), or if <paramref name="t"/> is not well-sorted.
/// In this case a <c>ModelEvaluationFailedException</c> is thrown.
/// </remarks>
/// <param name="t">An expression</param>
/// <param name="completion">
/// When this flag is enabled, a model value will be assigned to any constant
/// or function that does not have an interpretation in the model.
/// </param>
/// <returns>The evaluation of <paramref name="t"/> in the model.</returns>
public Expr Eval(Expr t, bool completion = false)
{
Contract.Requires(t != null);
Contract.Ensures(Contract.Result<Expr>() != null);
IntPtr v = IntPtr.Zero;
if (Native.Z3_model_eval(Context.nCtx, NativeObject, t.NativeObject, (completion) ? 1 : 0, ref v) == 0)
throw new ModelEvaluationFailedException();
else
return Expr.Create(Context, v);
}
/// <summary>
/// Array update.
/// </summary>
/// <remarks>
/// The node <c>a</c> must have an array sort <c>[domain -> range]</c>,
/// <c>i</c> must have sort <c>domain</c>,
/// <c>v</c> must have sort range. The sort of the result is <c>[domain -> range]</c>.
/// The semantics of this function is given by the theory of arrays described in the SMT-LIB
/// standard. See http://smtlib.org for more details.
/// The result of this function is an array that is equal to <c>a</c>
/// (with respect to <c>select</c>)
/// on all indices except for <c>i</c>, where it maps to <c>v</c>
/// (and the <c>select</c> of <c>a</c> with
/// respect to <c>i</c> may be a different value).
/// <seealso cref="MkArraySort"/>
/// <seealso cref="MkSelect"/>
/// </remarks>
public ArrayExpr MkStore(ArrayExpr a, Expr i, Expr v)
{
Contract.Requires(a != null);
Contract.Requires(i != null);
Contract.Requires(v != null);
Contract.Ensures(Contract.Result<ArrayExpr>() != null);
CheckContextMatch(a);
CheckContextMatch(i);
CheckContextMatch(v);
return new ArrayExpr(this, Native.Z3_mk_store(nCtx, a.NativeObject, i.NativeObject, v.NativeObject));
}
/// <summary>
/// Check for subsetness of sets.
/// </summary>
public Expr MkSetSubset(Expr arg1, Expr arg2)
{
Contract.Requires(arg1 != null);
Contract.Requires(arg2 != null);
Contract.Ensures(Contract.Result<Expr>() != null);
CheckContextMatch(arg1);
CheckContextMatch(arg2);
return Expr.Create(this, Native.Z3_mk_set_subset(nCtx, arg1.NativeObject, arg2.NativeObject));
}
/// <summary>
/// Check for set membership.
/// </summary>
public Expr MkSetMembership(Expr elem, Expr set)
{
Contract.Requires(elem != null);
Contract.Requires(set != null);
Contract.Ensures(Contract.Result<Expr>() != null);
CheckContextMatch(elem);
CheckContextMatch(set);
return Expr.Create(this, Native.Z3_mk_set_member(nCtx, elem.NativeObject, set.NativeObject));
}
/// <summary>
/// Remove an element from a set.
/// </summary>
public Expr MkSetDel(Expr set, Expr element)
{
Contract.Requires(set != null);
Contract.Requires(element != null);
Contract.Ensures(Contract.Result<Expr>() != null);
CheckContextMatch(set);
CheckContextMatch(element);
return Expr.Create(this, Native.Z3_mk_set_del(nCtx, set.NativeObject, element.NativeObject));
}
/// <summary>
/// Take the complement of a set.
/// </summary>
public Expr MkSetComplement(Expr arg)
{
Contract.Requires(arg != null);
Contract.Ensures(Contract.Result<Expr>() != null);
CheckContextMatch(arg);
return Expr.Create(this, Native.Z3_mk_set_complement(nCtx, arg.NativeObject));
}
/// <summary>
/// Array read.
/// </summary>
/// <remarks>
/// The argument <c>a</c> is the array and <c>i</c> is the index
/// of the array that gets read.
///
/// The node <c>a</c> must have an array sort <c>[domain -> range]</c>,
/// and <c>i</c> must have the sort <c>domain</c>.
/// The sort of the result is <c>range</c>.
/// <seealso cref="MkArraySort"/>
/// <seealso cref="MkStore"/>
/// </remarks>
public Expr MkSelect(ArrayExpr a, Expr i)
{
Contract.Requires(a != null);
Contract.Requires(i != null);
Contract.Ensures(Contract.Result<Expr>() != null);
CheckContextMatch(a);
CheckContextMatch(i);
return Expr.Create(this, Native.Z3_mk_select(nCtx, a.NativeObject, i.NativeObject));
}
/// <summary>
/// Create a Quantifier.
/// </summary>
public Quantifier MkQuantifier(bool universal, Expr[] boundConstants, Expr body, uint weight = 1, Pattern[] patterns = null, Expr[] noPatterns = null, Symbol quantifierID = null, Symbol skolemID = null)
{
Contract.Requires(body != null);
Contract.Requires(boundConstants == null || Contract.ForAll(boundConstants, n => n != null));
Contract.Requires(patterns == null || Contract.ForAll(patterns, p => p != null));
Contract.Requires(noPatterns == null || Contract.ForAll(noPatterns, np => np != null));
Contract.Ensures(Contract.Result<Quantifier>() != null);
if (universal)
return MkForall(boundConstants, body, weight, patterns, noPatterns, quantifierID, skolemID);
else
return MkExists(boundConstants, body, weight, patterns, noPatterns, quantifierID, skolemID);
}