public static Expression CreateParenthesized(Context cx, VarPatternSyntax varPattern, ParenthesizedVariableDesignationSyntax designation, IExpressionParentEntity parent, int child)
{
var type = NullType.Create(cx); // Should ideally be a corresponding tuple type
var tuple = new Expression(new ExpressionInfo(cx, type, cx.Create(varPattern.GetLocation()), ExprKind.TUPLE, parent, child, false, null));
cx.Try(null, null, () =>
{
var child0 = 0;
foreach (var variable in designation.Variables)
{
switch (variable)
{
case ParenthesizedVariableDesignationSyntax paren:
CreateParenthesized(cx, varPattern, paren, tuple, child0++);
break;
case SingleVariableDesignationSyntax single:
if (cx.GetModel(variable).GetDeclaredSymbol(single) is ILocalSymbol local)
{
var decl = Create(cx, variable, Entities.Type.Create(cx, local.GetAnnotatedType()), true, tuple, child0++);
var id = single.Identifier;
var location = cx.Create(id.GetLocation());
LocalVariable.Create(cx, local, decl, true, location);
}
else
{
throw new InternalError(single, "Failed to access local variable");
}
break;
case DiscardDesignationSyntax discard:
new Discard(cx, discard, tuple, child0++);
break;
default:
throw new InternalError(variable, "Unhandled designation type");
}
}
});
return(tuple);
}
public static Expression CreateParenthesized(Context cx, VarPatternSyntax varPattern, ParenthesizedVariableDesignationSyntax designation, IExpressionParentEntity parent, int child)
{
var tuple = new Expression(
new ExpressionInfo(cx, null, cx.CreateLocation(varPattern.GetLocation()), ExprKind.TUPLE, parent, child, false, null),
shouldPopulate: false);
var elementTypes = new List <ITypeSymbol?>();
cx.Try(null, null, () =>
{
var child0 = 0;
foreach (var variable in designation.Variables)
{
Expression sub;
switch (variable)
{
case ParenthesizedVariableDesignationSyntax paren:
sub = CreateParenthesized(cx, varPattern, paren, tuple, child0++);
break;
case SingleVariableDesignationSyntax single:
if (cx.GetModel(variable).GetDeclaredSymbol(single) is ILocalSymbol local)
{
var decl = Create(cx, variable, local.GetAnnotatedType(), tuple, child0++);
var l = LocalVariable.Create(cx, local);
l.PopulateManual(decl, true);
sub = decl;
}
else
{
throw new InternalError(single, "Failed to access local variable");
}
break;
case DiscardDesignationSyntax discard:
sub = new Discard(cx, discard, tuple, child0++);
if (!sub.Type.HasValue || sub.Type.Value.Symbol is null)
{
// The type is only updated in memory, it will not be written to the trap file.
sub.SetType(cx.Compilation.GetSpecialType(SpecialType.System_Object));
}
break;
default:
var type = variable.GetType().ToString() ?? "null";
throw new InternalError(variable, $"Unhandled designation type {type}");
}
elementTypes.Add(sub.Type.HasValue && sub.Type.Value.Symbol?.Kind != SymbolKind.ErrorType
? sub.Type.Value.Symbol
: null);
}
});
INamedTypeSymbol?tupleType = null;
if (!elementTypes.Any(et => et is null))
{
tupleType = cx.Compilation.CreateTupleTypeSymbol(elementTypes.ToImmutableArray() !);
}
tuple.SetType(tupleType);
tuple.TryPopulate();
return(tuple);
}