public static Expression Create(ExpressionNodeInfo info)
{
var symbolInfo = info.Context.GetSymbolInfo(info.Node);
var target = symbolInfo.Symbol;
if (target == null && symbolInfo.CandidateReason == CandidateReason.OverloadResolutionFailure)
{
// The expression is probably a cast
target = info.Context.GetSymbolInfo((CSharpSyntaxNode)info.Node.Parent).Symbol;
}
if (target == null && (symbolInfo.CandidateReason == CandidateReason.Ambiguous || symbolInfo.CandidateReason == CandidateReason.MemberGroup))
{
// Pick one at random - they probably resolve to the same ID
target = symbolInfo.CandidateSymbols.First();
}
if (target == null)
{
info.Context.ModelError(info.Node, "Failed to resolve name");
return(new Unknown(info));
}
// There is a very strange bug in Microsoft.CodeAnalysis whereby
// target.Kind throws System.InvalidOperationException for Discard symbols.
// So, short-circuit that test here.
// Ideally this would be another case in the switch statement below.
if (target is IDiscardSymbol)
{
return(new Discard(info));
}
switch (target.Kind)
{
case SymbolKind.TypeParameter:
case SymbolKind.NamedType:
case SymbolKind.DynamicType:
return(TypeAccess.Create(info));
case SymbolKind.Property:
case SymbolKind.Field:
case SymbolKind.Event:
case SymbolKind.Method:
return(Access.Create(info, target, true, info.Context.CreateEntity(target)));
case SymbolKind.Local:
case SymbolKind.RangeVariable:
return(Access.Create(info, target, false, LocalVariable.GetAlreadyCreated(info.Context, target)));
case SymbolKind.Parameter:
return(Access.Create(info, target, false, Parameter.GetAlreadyCreated(info.Context, (IParameterSymbol)target)));
case SymbolKind.Namespace:
return(Access.Create(info, target, false, Namespace.Create(info.Context, (INamespaceSymbol)target)));
default:
throw new InternalError(info.Node, $"Unhandled identifier kind '{target.Kind}'");
}
}
protected Expression DeclareRangeVariable(Context cx, IExpressionParentEntity parent, int child, bool getElement, ISymbol variableSymbol, SyntaxToken name)
{
var type = Type.Create(cx, cx.GetType(Expr));
Extraction.Entities.Location nameLoc;
Type declType;
TypeSyntax declTypeSyntax = null;
if (getElement)
{
var from = node as FromClauseSyntax;
(declType, declTypeSyntax) = from != null && from.Type != null
? (Type.Create(cx, cx.GetType(from.Type)), from.Type)
: (type.ElementType, null);
}
else
{
declType = type;
}
var decl = VariableDeclaration.Create(cx,
variableSymbol,
declType,
declTypeSyntax,
cx.Create(node.GetLocation()),
nameLoc = cx.Create(name.GetLocation()),
true,
parent,
child
);
Expression.Create(cx, Expr, decl, 0);
var access = new Expression(new ExpressionInfo(cx, type, nameLoc, ExprKind.LOCAL_VARIABLE_ACCESS, decl, 1, false, null));
cx.Emit(Tuples.expr_access(access, LocalVariable.GetAlreadyCreated(cx, variableSymbol)));
return(decl);
}