protected MethodResolutionException(MethodInfo originalSignature, MethodInfo inferredSignature, TypeInferenceEngine engine, int? mismatchIndex, Exception innerException)
: base(innerException)
{
OriginalSignature = originalSignature;
InferredSignature = inferredSignature;
RootExpression = engine.Root;
MismatchIndex = mismatchIndex;
try
{
// ensure that all call args are inferred successfully
foreach (var arg in engine.Root.CallArgs())
{
// we need this check because depending on the context
// call args might already be inferred by the moment of crash
if (!engine.Inferences.ContainsKey(arg))
{
// this is unlikely to crash and ruin our attempt to provide the client with comprehensive info
// since type inference for arguments has already been probed before entering TypeInferenceMethods.Resolve
engine.InferTypes(arg);
}
}
ActualArguments = engine.Ctx.Root.ToXArgs(engine.Inferences).ToArray();
FormalArguments = (InferredSignature ?? OriginalSignature).ToXArgs(ActualArguments.Length).ToArray();
// the lines below are copy&pasted from GenericArgsInference.cs
for (var i = 0; i < ActualArguments.Length; ++i)
{
var ai_r = ActualArguments.ElementAt(i);
var pi = FormalArguments.ElementAt(i);
if (!pi.IsOpenGeneric())
{
if (pi.IsFunctionType() && ai_r is Lambda)
{
var ai_s = ((Lambda)ai_r).Type.GetFunctionSignature();
var pi_s = pi.GetFunctionSignature();
if (ai_s.GetParameters().Length == pi_s.GetParameters().Length)
{
var callArg = engine.Ctx.Root.CallArgs().ElementAt(i - 1);
ActualArguments[i] = new Lambda(
(LambdaExpression)callArg,
(pi_s.GetParameters()
.Select(pi2 => pi2.ParameterType.IsGenericParameter ?
typeof(Variant) : pi2.ParameterType)
.Concat(typeof(Variant).AsArray()))
.ForgeFuncType());
}
}
}
}
}
catch (Exception)
{
// sigh, the client won't get full info from the crash site
// sad, but true, so just ignore possible exceptions
}
}
private void InferMethodGroup(MethodGroup mg, RelinqScriptExpression root, TypeInferenceCache cache)
{
// q: should existing but not accessible (security!) methods be included into the resolution?
// a: yes and here's why:
// scenario 1. Included; when overload resolution binds to an unauthorized method = crash.
// scenario 2. Not included, so overload resolution binds to an unexpected method = fail.
// lets us the fail fast if the resolution is unnecessary.
// inferences made here won't be wasted anyways since they get cached
var ctx = new TypeInferenceContext(root, cache, Integration);
var preview = new TypeInferenceEngine(ctx);
root.CallArgs().ForEach(child => preview.InferTypes(child));
// we cannot pass the preview.Ctx inside since it might have
// potentially half-inferred lambdas that won't be able to be reinferred
// by MG resolution since ctx is init only.
var resolved = mg.Resolve(ctx);
cache.Add(root, resolved.Signature.ReturnType);
cache.Invocations.Add(root, resolved);
cache.Upgrade(resolved.Inferences);
}
public Expression Compile(String relinqScriptCode)
{
var ast = new RelinqScriptParser(relinqScriptCode, Integration).Parse();
var inferences = new TypeInferenceEngine(ast, Integration).InferTypes();
return new CSharpExpressionTreeBuilder(ast, Integration).Compile(inferences);
}
public GenericArgumentsInferenceException(GenericArgumentsInferenceExceptionType type, MethodInfo originalSignature, MethodInfo inferredSignature, TypeInferenceEngine engine, int? mismatchIndex, Exception innerException)
: base(originalSignature, inferredSignature, engine, mismatchIndex, innerException)
{
Type = type;
}
public GenericArgumentsInferenceException(GenericArgumentsInferenceExceptionType type, MethodInfo originalSignature, MethodInfo inferredSignature, TypeInferenceEngine engine, Exception innerException)
: this(type, originalSignature, inferredSignature, engine, null, innerException)
{
}
public GenericArgumentsInferenceException(GenericArgumentsInferenceExceptionType type, MethodInfo originalSignature, MethodInfo inferredSignature, TypeInferenceEngine engine, int? mismatchIndex)
: this(type, originalSignature, inferredSignature, engine, mismatchIndex, null)
{
}
public static MethodInfo InferGenericTypeParams(this MethodInfo mi, TypeInferenceContext ctx)
{
var originalSignature = mi;
TypeInferenceEngine preview = null;
try
{
preview = new TypeInferenceEngine(ctx);
ctx.Root.CallArgs().ForEach(child => preview.InferTypes(child));
var fail = Array.FindIndex(ctx.Root.CallArgs().ToArray(), c => preview.Inferences[c] is Variant);
if (fail != -1)
{
throw new GenericArgumentsInferenceException(
GenericArgumentsInferenceExceptionType.VariantArg,
originalSignature, mi, preview, fail);
}
else
{
Func<IEnumerable<RelinqScriptType>> args = () => ctx.Root.ToXArgs(preview.Inferences);
Func<IEnumerable<Type>> @params = () => mi.ToXArgs(args().Count());
var argc = args().Count();
if (argc != @params().Count())
{
throw new GenericArgumentsInferenceException(
GenericArgumentsInferenceExceptionType.ArgcMismatch,
originalSignature, mi, preview);
}
else
{
var processed = new TrackableList<bool>(Enumerable.Repeat(false, argc));
var fresh = new List<bool>(Enumerable.Repeat(true, argc));
processed.ListChanged += (o, e) => fresh[e.Index] = true;
while (fresh.Any(b => b) && !processed.All(b => b))
{
Enumerable.Range(0, argc).ForEach(i => fresh[i] = false);
foreach (var i in processed.ToArray()
.Select((b, j) => new { b, j }).Where(_ => !_.b).Select(_ => _.j))
{
var ai_r = args().ElementAt(i);
var pi = @params().ElementAt(i);
var argIndex = mi.IsExtension() ? i : i - 1;
if (!pi.IsOpenGeneric())
{
if (pi.IsFunctionType() && ai_r is Lambda)
{
var ai_s = ((Lambda)ai_r).Type.GetFunctionSignature();
var pi_s = pi.GetFunctionSignature();
// todo. support varargs here as well
if (ai_s.GetParameters().Length == pi_s.GetParameters().Length)
{
var preview2 = new TypeInferenceEngine(ctx);
// todo. the line below is only possible because we don't process lambda extension calls
var callArg = ctx.Root.CallArgs().ElementAt(i - 1);
preview2.Ctx.Inferences.Add(callArg, new Lambda(
(LambdaExpression)callArg,
(pi_s.GetParameters()
.Select(pi2 => pi2.ParameterType.IsGenericParameter ?
typeof(Variant) : pi2.ParameterType)
.Concat(typeof(Variant).AsArray()))
.ForgeFuncType()));
try
{
preview2.InferTypes(callArg);
}
catch (RelinqException rex)
{
if (rex.IsUnexpected)
{
throw;
}
else
{
throw new GenericArgumentsInferenceException(
GenericArgumentsInferenceExceptionType.LambdaInconsistentBody,
originalSignature, mi, preview, i, rex);
}
}
catch (Exception ex)
{
throw new GenericArgumentsInferenceException(
GenericArgumentsInferenceExceptionType.Unexpected,
originalSignature, mi, preview, i, ex);
}
var lambdaBody = ((LambdaExpression)callArg).Body;
var retval = preview2.Inferences[lambdaBody];
if (retval is ClrType)
{
var ai_ret = ((ClrType)retval).Type;
var pi_ret = pi_s.ReturnType;
if (!ai_ret.HasImplicitCastTo(pi_ret))
{
throw new GenericArgumentsInferenceException(
GenericArgumentsInferenceExceptionType.LambdaIncompatibleRetval,
originalSignature, mi, preview, i);
}
}
else
{
// lambdas that return lambdas or method groups
// are not implemented, since they're not supported by C# spec.
throw new GenericArgumentsInferenceException(
GenericArgumentsInferenceExceptionType.LambdaInvalidRetval,
originalSignature, mi, preview, i);
}
}
else
{
throw new GenericArgumentsInferenceException(
GenericArgumentsInferenceExceptionType.LambdaArgcMismatch,
originalSignature, mi, preview, i);
}
}
processed[i] = true;
}
else
{
if (ai_r is ClrType)
{
var ai = ((ClrType)ai_r).Type;
// todo. also check implicit casts here?
var inf = ai.LookupInheritanceChain()
.Select(aij => pi.InferFrom(aij))
.FirstOrDefault(inf2 => inf2 != null);
if (inf != null)
{
mi = mi.InferStructuralUnits(inf.ToDictionary(
kvp => "a" + argIndex + kvp.Key,
kvp => kvp.Value));
if (mi != null)
{
processed[i] = true;
}
else
{
throw new GenericArgumentsInferenceException(
GenericArgumentsInferenceExceptionType.InferencesContradictGenericConstraints,
originalSignature, mi, preview, i);
}
}
else
{
throw new GenericArgumentsInferenceException(
GenericArgumentsInferenceExceptionType.FormalArgCannotBeInferredFromActualArg,
originalSignature, mi, preview, i);
}
}
else if (ai_r is Lambda)
{
if (pi.IsFunctionType())
{
var ai_s = ((Lambda)ai_r).Type.GetFunctionSignature();
var pi_s = pi.GetFunctionSignature();
// todo. support varargs here as well
if (ai_s.GetParameters().Length == pi_s.GetParameters().Length)
{
var preview2 = new TypeInferenceEngine(ctx);
// todo. the line below is only possible because we don't process lambda extension calls
var callArg = ctx.Root.CallArgs().ElementAt(i - 1);
preview2.Ctx.Inferences.Add(callArg, new Lambda(
(LambdaExpression)callArg,
(pi_s.GetParameters()
.Select(pi2 => pi2.ParameterType.IsGenericParameter ?
typeof(Variant) : pi2.ParameterType)
.Concat(typeof(Variant).AsArray()))
.ForgeFuncType()));
try
{
preview2.InferTypes(callArg);
}
catch (RelinqException rex)
{
if (rex.IsUnexpected)
{
throw;
}
else
{
throw new GenericArgumentsInferenceException(
GenericArgumentsInferenceExceptionType.LambdaInconsistentBody,
originalSignature, mi, preview, i, rex);
}
}
catch (Exception ex)
{
throw new GenericArgumentsInferenceException(
GenericArgumentsInferenceExceptionType.Unexpected,
originalSignature, mi, preview, i, ex);
}
var lambdaBody = ((LambdaExpression)callArg).Body;
var retval = preview2.Inferences[lambdaBody];
if (retval is ClrType)
{
var ai_ret = ((ClrType)retval).Type;
var pi_ret = pi_s.ReturnType;
if (pi_ret.IsOpenGeneric())
{
var inf = ai_ret.LookupInheritanceChain()
.Select(ai_retj => pi_ret.InferFrom(ai_retj))
.FirstOrDefault(inf2 => inf2 != null);
if (inf != null)
{
var map = pi.GetStructuralTree();
mi = mi.InferStructuralUnits(inf.ToDictionary(
kvp => "a" + argIndex + map.Single(kvp2 =>
kvp2.Value == pi_ret.SelectStructuralUnit(kvp.Key)).Key,
kvp => kvp.Value));
if (mi != null)
{
processed[i] = true;
}
else
{
throw new GenericArgumentsInferenceException(
GenericArgumentsInferenceExceptionType.InferencesContradictGenericConstraints,
originalSignature, mi, preview, i);
}
}
else
{
throw new GenericArgumentsInferenceException(
GenericArgumentsInferenceExceptionType.FormalArgCannotBeInferredFromActualArg,
originalSignature, mi, preview, i);
}
}
else
{
processed[i] = true;
}
}
else if (retval is Variant)
{
continue;
}
// lambdas that return lambdas or method groups
// are not implemented, since they're not supported by C# spec.
else
{
throw new GenericArgumentsInferenceException(
GenericArgumentsInferenceExceptionType.LambdaInvalidRetval,
originalSignature, mi, preview, i);
}
}
else
{
throw new GenericArgumentsInferenceException(
GenericArgumentsInferenceExceptionType.LambdaArgcMismatch,
originalSignature, mi, preview, i);
}
}
else
{
throw new GenericArgumentsInferenceException(
GenericArgumentsInferenceExceptionType.FormalArgCannotBeInferredFromActualArg,
originalSignature, mi, preview, i);
}
}
// unlike lambdas, method groups don't participate in type args inference
// neither they can help to infer type args,
// nor can they be inferred themselves.
else
{
processed[i] = true;
}
}
}
}
if (!mi.IsOpenGeneric())
{
return mi;
}
else
{
throw new GenericArgumentsInferenceException(
GenericArgumentsInferenceExceptionType.IncompleteInferenceSet,
originalSignature, mi, preview);
}
}
}
}
catch (GenericArgumentsInferenceException)
{
throw;
}
catch (Exception ex)
{
throw new GenericArgumentsInferenceException(
GenericArgumentsInferenceExceptionType.Unexpected,
originalSignature, mi, preview ?? new TypeInferenceEngine(ctx), ex);
}
}
// todo. resolve the method group -> delegate cast
// and also provide generic arg inference altogether
public static ResolvedInvocation Resolve(this MethodGroup mg, TypeInferenceContext ctx)
{
var failboats = new Dictionary<MethodInfo, MethodResolutionException>();
var infToOrig = new Dictionary<MethodInfo, MethodInfo>();
var origToInf = new Dictionary<MethodInfo, MethodInfo>();
try
{
// Step 1. Get rid of alternatives that don't have a form that suits arg count.
var suitableAlts = new List<MethodInfo>();
foreach (var alt in mg.Alts)
{
if (alt.XArgsCount().Contains(ctx.Root.XArgsCount()))
{
suitableAlts.Add(alt);
}
else
{
failboats.Add(alt, new MethodMatchingException(
MethodMatchingExceptionType.ArgcMismatch, alt, null, ctx));
}
}
// Step 2. Infer generic arguments of all open generic alternatives and get rid of those who fail to be inferred.
var inferredAlts = new List<MethodInfo>();
foreach (var salt in suitableAlts)
{
try
{
var infAlt = salt.InferGenericTypeParams(ctx);
inferredAlts.Add(infAlt);
origToInf.Add(salt, infAlt);
infToOrig.Add(infAlt, salt);
}
catch (GenericArgumentsInferenceException gex)
{
if (gex.IsUnexpected)
{
throw;
}
else
{
failboats.Add(salt, new MethodMatchingException(
MethodMatchingExceptionType.GenericArgInferenceFailed, salt, null, ctx, gex));
}
}
}
// Step 3. Store type inference context of all alternatives that had made it so far
var sigs = new List<ResolvedSignature>();
foreach (var infAlt in inferredAlts)
{
var infAlt1 = infAlt;
var resolvedCtx = new TypeInferenceEngine(ctx);
ctx.Root.CallArgs().ForEach((callArg, i) =>
{
if (callArg is LambdaExpression)
{
var inferredFormal = infAlt1.IsExtension()
? infAlt1.GetParameters()[i + 1].ParameterType
: infAlt1.GetParameters()[i].ParameterType;
var inferredLambda = new Lambda(
(LambdaExpression)callArg, inferredFormal.NormalizeFunctionType());
resolvedCtx.Ctx.Inferences.Add(callArg, inferredLambda);
}
resolvedCtx.InferTypes(callArg);
});
sigs.Add(new ResolvedSignature(resolvedCtx.Ctx, infAlt));
}
// Step 4. Now get rid of alternatives that do not match Relinq-specific validation
var validSigs = new List<ResolvedSignature>();
foreach (var sig in sigs)
{
var args = ctx.Root.ToXArgs(sig.Inferences);
if (sig.Signature.IsValid(sig.Signature.IsExtension() ? args : args.Skip(1)))
{
validSigs.Add(sig);
}
else
{
failboats.Add(infToOrig[sig.Signature], new MethodMatchingException(
MethodMatchingExceptionType.SignatureFailsMetaConstrains, infToOrig[sig.Signature], sig.Signature, ctx));
}
}
// Step 5. Eliminate signatures that do not satisfy actual argument conversions
var invs = new List<ResolvedInvocation>();
foreach (var validSig in validSigs)
{
var args = ctx.Root.ToXArgs(validSig.Inferences);
var @params = validSig.Signature.ToXArgs(ctx.Root.XArgsCount());
var inv = new ResolvedInvocation(validSig, args.Zip(@params, (arg, param) => Cast.Lookup(arg, param)));
var fail = Array.FindIndex(inv.Casts.ToArray(), c => c == null);
if (fail == -1)
{
invs.Add(inv);
}
else
{
failboats.Add(infToOrig[validSig.Signature], new MethodMatchingException(
MethodMatchingExceptionType.ActualArgCannotBeCastToFormalArg, infToOrig[validSig.Signature], validSig.Signature, ctx, fail));
}
}
// Step 6. Remove sub-par signatures from the all-satisfying survivors
var res = new List<ResolvedInvocation>();
foreach (var inv in invs)
{
var subpar = false;
foreach (var anotherInv in invs)
{
subpar |= anotherInv > inv;
}
if (!subpar)
{
res.Add(inv);
}
else
{
failboats.Add(infToOrig[inv.Signature], new MethodMatchingException(
MethodMatchingExceptionType.SignatureIsSubPar, infToOrig[inv.Signature], inv.Signature, ctx));
}
}
// Step 7. Finalize the death race (and evade the final trap)
switch (res.Count())
{
case 0:
throw new MethodGroupResolutionFailedException(
JSToCSharpExceptionType.FruitlessMethodGroupResolution, mg, failboats, ctx);
case 1:
var winrar = res.Single();
if (winrar.Signature.IsTrap())
{
failboats.Add(infToOrig[winrar.Signature], new MethodMatchingException(
MethodMatchingExceptionType.SignatureIsEntrapped, infToOrig[winrar.Signature], winrar.Signature, ctx));
throw new MethodGroupResolutionFailedException(
JSToCSharpExceptionType.FruitlessMethodGroupResolution, mg, failboats, ctx);
}
// my sincere congratulations
return winrar;
default:
foreach (var winrar2 in res)
{
failboats.Add(infToOrig[winrar2.Signature], new MethodMatchingException(
MethodMatchingExceptionType.SignatureIsOkButAmbiguous, infToOrig[winrar2.Signature], winrar2.Signature, ctx));
}
throw new MethodGroupResolutionFailedException(
JSToCSharpExceptionType.AmbiguousMethodGroupResolution, mg, failboats, ctx);
}
}
catch (MethodGroupResolutionFailedException)
{
throw;
}
catch (Exception ex)
{
throw new MethodGroupResolutionFailedException(
JSToCSharpExceptionType.Unexpected, mg, failboats, ctx, ex);
}
}
protected MethodResolutionException(MethodInfo originalSignature, MethodInfo inferredSignature, TypeInferenceEngine engine, Exception innerException)
: this(originalSignature, inferredSignature, engine, null, innerException)
{
}
protected MethodResolutionException(MethodInfo originalSignature, MethodInfo inferredSignature, TypeInferenceEngine engine, int? mismatchIndex)
: this(originalSignature, inferredSignature, engine, mismatchIndex, null)
{
}