public override Conversion ClassifyConversion(LanguageSyntaxNode expression, ITypeSymbol destination, bool isExplicitInSource = false)
{
var csdestination = destination.EnsureLanguageSymbolOrNull <ITypeSymbol, TypeSymbol>(nameof(destination));
if (isExplicitInSource)
{
return(ClassifyConversionForCast(expression, csdestination));
}
CheckSyntaxNode(expression);
if ((object)destination == null)
{
throw new ArgumentNullException(nameof(destination));
}
// TODO(cyrusn): Check arguments. This is a public entrypoint, so we must do appropriate
// checks here. However, no other methods in this type do any checking currently. So I'm
// going to hold off on this until we do a full sweep of the API.
var model = this.GetMemberModel(expression);
if (model == null)
{
// 'expression' must just be reference to a type or namespace name outside of an
// expression context. Currently we bail in that case. However, is this a question
// that a client would be asking and would expect sensible results for?
return(Conversion.NoConversion);
}
return(model.ClassifyConversion(expression, destination));
}
public override Conversion ClassifyConversion(
LanguageSyntaxNode expression,
ITypeSymbol destination,
bool isExplicitInSource = false)
{
if ((object)destination == null)
{
throw new ArgumentNullException(nameof(destination));
}
var csdestination = destination.EnsureLanguageSymbolOrNull <ITypeSymbol, TypeSymbol>(nameof(destination));
if (isExplicitInSource)
{
return(ClassifyConversionForCast(expression, csdestination));
}
// Note that it is possible for an expression to be convertible to a type
// via both an implicit user-defined conversion and an explicit built-in conversion.
// In that case, this method chooses the implicit conversion.
CheckSyntaxNode(expression);
var binder = this.GetEnclosingBinderInternal(expression, GetAdjustedNodePosition(expression));
LanguageSyntaxNode bindableNode = this.GetBindableSyntaxNode(expression);
var boundExpression = this.GetLowerBoundNode(bindableNode) as BoundExpression;
if (binder == null || boundExpression == null)
{
return(Conversion.NoConversion);
}
HashSet <DiagnosticInfo> useSiteDiagnostics = null;
return(binder.Conversions.ClassifyConversionFromExpression(boundExpression, csdestination, ref useSiteDiagnostics));
}