} // func MemberGetSandbox
private static Expression MemberGetExpressionCore(Lua lua, Token tokenStart, Expression instance, string memberName)
{
// if this is a dynamic type, let the type deside what is to do
if (LuaEmit.IsDynamicType(instance.Type))
{
return(DynamicExpression.Dynamic(lua.GetGetMemberBinder(memberName), typeof(object), ConvertObjectExpression(lua, tokenStart, instance, true)));
}
else
{
Expression result;
switch (LuaEmit.TryGetMember(instance, instance.Type, memberName, false, out result))
{
case LuaTryGetMemberReturn.None:
throw ParseError(tokenStart, LuaEmitException.GetMessageText(LuaEmitException.MemberNotFound, instance.Type.Name, memberName));
case LuaTryGetMemberReturn.NotReadable:
throw ParseError(tokenStart, LuaEmitException.GetMessageText(LuaEmitException.CanNotReadMember, instance.Type.Name, memberName));
case LuaTryGetMemberReturn.ValidExpression:
return(result);
default:
throw new ArgumentException("Internal return type of TryGetMember");
}
}
} // func MemberGetExpressionCore
} // ctor
public override DynamicMetaObject FallbackGetMember(DynamicMetaObject target, DynamicMetaObject errorSuggestion)
{
// defer the target, to get the type
if (!target.HasValue)
{
return(Defer(target));
}
if (target.Value == null) // no value for target, finish binding with an error or the suggestion
{
return(errorSuggestion ??
new DynamicMetaObject(
ThrowExpression(Resources.rsNullReference, ReturnType),
target.Restrictions.Merge(BindingRestrictions.GetInstanceRestriction(target.Expression, null))
));
}
else
{
Expression expr;
// restrictions
var restrictions = target.Restrictions.Merge(BindingRestrictions.GetTypeRestriction(target.Expression, target.LimitType));
// try to bind the member
switch (LuaEmit.TryGetMember(target.Expression, target.LimitType, Name, IgnoreCase, out expr))
{
case LuaTryGetMemberReturn.None:
return(errorSuggestion ?? new DynamicMetaObject(Expression.Default(ReturnType), restrictions));
case LuaTryGetMemberReturn.NotReadable:
return(errorSuggestion ?? new DynamicMetaObject(ThrowExpression(LuaEmitException.GetMessageText(LuaEmitException.CanNotReadMember, target.LimitType.Name, Name), ReturnType), restrictions));
case LuaTryGetMemberReturn.ValidExpression:
return(new DynamicMetaObject(Lua.EnsureType(expr, ReturnType), restrictions));
default:
throw new ArgumentException("return of TryGetMember.");
}
}
} // func FallbackGetMember