private BoundExpression VisitExpressionImpl(BoundExpression node)
{
ConstantValue constantValue = node.ConstantValue;
if (constantValue != null)
{
TypeSymbol type = node.Type;
if (type?.IsNullableType() != true)
{
return(MakeLiteral(node.Syntax, constantValue, type));
}
}
var visited = VisitExpressionWithStackGuard(node);
// If you *really* need to change the type, consider using an indirect method
// like compound assignment does (extra flag only passed when it is an expression
// statement means that this constraint is not violated).
// Dynamic type will be erased in emit phase. It is considered equivalent to Object in lowered bound trees.
// Unused deconstructions are lowered to produce a return value that isn't a tuple type.
#if XSHARP
Debug.Assert(visited == null || visited.HasErrors || ReferenceEquals(visited.Type, node.Type) ||
visited.Type.Equals(node.Type, TypeCompareKind.IgnoreDynamicAndTupleNames) ||
IsUnusedDeconstruction(node) ||
(_compilation.Options.HasRuntime && node?.Type == _compilation.UsualType()));
#else
Debug.Assert(visited == null || visited.HasErrors || ReferenceEquals(visited.Type, node.Type) ||
visited.Type.Equals(node.Type, TypeCompareKind.IgnoreDynamicAndTupleNames) ||
IsUnusedDeconstruction(node));
#endif
if (visited != null && visited != node)
{
if (!CanBePassedByReference(node) && CanBePassedByReference(visited))
{
visited = RefAccessMustMakeCopy(visited);
}
}
return(visited);
}
