/// <inheritdoc/>
public override ITypeMember Decode(LNode data, DecoderState state)
{
if (data.Calls(accessorSymbol))
{
if (!FeedbackHelpers.AssertArgCount(data, 2, state.Log) ||
!FeedbackHelpers.AssertIsId(data.Args[1], state.Log))
{
return(null);
}
var property = state.DecodeProperty(data.Args[0]);
if (property == null)
{
return(null);
}
else
{
var kindName = data.Args[1].Name.Name;
var accessor = property.Accessors.FirstOrDefault(
acc => accessorKindEncodings[acc.Kind] == kindName);
if (accessor == null)
{
FeedbackHelpers.LogSyntaxError(
state.Log,
data.Args[1],
Quotation.QuoteEvenInBold(
"property ",
FeedbackHelpers.Print(data.Args[0]),
" does not define a ",
kindName,
" accessor."));
}
return(accessor);
}
}
else if (data.Calls(CodeSymbols.Dot))
{
// Simple dot indicates a field.
IType parentType;
SimpleName name;
if (!AssertDecodeTypeAndName(data, state, out parentType, out name))
{
return(null);
}
var candidates = state.TypeMemberIndex
.GetAll(parentType, name)
.OfType <IField>()
.ToArray();
return(CheckSingleCandidate(
candidates,
data.Args[0],
data.Args[1],
"field",
state));
}
else if (data.CallsMin(CodeSymbols.IndexBracks, 1))
{
IType parentType;
SimpleName name;
if (!AssertDecodeTypeAndName(data.Args[0], state, out parentType, out name))
{
return(null);
}
var indexTypes = data.Args
.Slice(1)
.EagerSelect(state.DecodeType);
var candidates = state.TypeMemberIndex
.GetAll(parentType, name)
.OfType <IProperty>()
.Where(prop =>
prop.IndexerParameters
.Select(p => p.Type)
.SequenceEqual(indexTypes))
.ToArray();
return(CheckSingleCandidate(
candidates,
data.Args[0].Args[0],
data,
"property",
state));
}
else if (data.Calls(CodeSymbols.Lambda))
{
IType parentType;
SimpleName name;
if (!FeedbackHelpers.AssertArgCount(data, 2, state.Log) ||
!FeedbackHelpers.AssertIsCall(data.Args[0], state.Log) ||
!AssertDecodeTypeAndName(data.Args[0].Target, state, out parentType, out name))
{
return(null);
}
// TODO: implement generic parameter decoding, use generic
// parameters in resolution process.
var paramTypes = data.Args[0].Args
.EagerSelect(state.DecodeType);
var retType = state.DecodeType(data.Args[1]);
var candidates = state.TypeMemberIndex
.GetAll(parentType, name)
.OfType <IMethod>()
.Where(method =>
method.Parameters
.Select(p => p.Type)
.SequenceEqual(paramTypes) &&
object.Equals(
method.ReturnParameter.Type,
retType))
.ToArray();
return(CheckSingleCandidate(
candidates,
data.Args[0].Target.Args[0],
data,
"method",
state));
}
else if (data.Calls(CodeSymbols.Of))
{
if (!FeedbackHelpers.AssertMinArgCount(data, 1, state.Log))
{
return(null);
}
var func = state.DecodeMethod(data.Args[0]);
var args = data.Args.Slice(1).EagerSelect(state.DecodeType);
if (func.GenericParameters.Count == args.Count)
{
return(func.MakeGenericMethod(args));
}
else
{
state.Log.LogSyntaxError(
data,
Quotation.QuoteEvenInBold(
"generic arity mismatch; expected ",
func.GenericParameters.Count.ToString(),
" parameters but got ",
args.Count.ToString(),
"."));
return(null);
}
}
else
{
state.Log.LogSyntaxError(
data,
Quotation.QuoteEvenInBold(
"cannot interpret ",
FeedbackHelpers.Print(data),
" as a type member; expected a call to one of ",
accessorSymbol.Name, ", ",
CodeSymbols.Dot.Name, ", ",
CodeSymbols.IndexBracks.Name, ", ",
CodeSymbols.Of.Name, " or ",
CodeSymbols.Lambda.Name));
return(null);
}
}
