public object Askfor(String typeName)
{
if (typeName == null)
{
UserInterface.ShowMsgAskForEnter("Pause..");
return(null);
}
if (TypesHelper.GetNodeOrEdgeType(typeName, impl.curShellProcEnv.ProcEnv.NamedGraph.Model) != null) // if type is node/edge type let the user select the element in yComp
{
if (!CheckDebuggerAlive())
{
impl.errOut.WriteLine("debug mode must be enabled (yComp available) for asking for a node/edge type");
return(null);
}
impl.debugOut.WriteLine("Select an element of type " + typeName + " by double clicking in yComp (ESC for abort)...");
String id = debugger.ChooseGraphElement();
if (id == null)
{
return(null);
}
impl.debugOut.WriteLine("Received @(\"" + id + "\")");
IGraphElement elem = impl.curShellProcEnv.ProcEnv.NamedGraph.GetGraphElement(id);
if (elem == null)
{
impl.errOut.WriteLine("Graph element does not exist (anymore?).");
return(null);
}
if (!TypesHelper.IsSameOrSubtype(elem.Type.PackagePrefixedName, typeName, impl.curShellProcEnv.ProcEnv.NamedGraph.Model))
{
impl.errOut.WriteLine(elem.Type.PackagePrefixedName + " is not the same type as/a subtype of " + typeName + ".");
return(null);
}
return(elem);
}
else // else let the user type in the value
{
String inputValue = UserInterface.ShowMsgAskForString("Enter a value of type " + typeName + ": ");
StringReader reader = new StringReader(inputValue);
GrShell shellForParsing = new GrShell(reader);
shellForParsing.SetImpl(impl.GetGrShellImpl());
object val = shellForParsing.Constant();
String valTypeName = TypesHelper.XgrsTypeOfConstant(val, impl.curShellProcEnv.ProcEnv.NamedGraph.Model);
if (!TypesHelper.IsSameOrSubtype(valTypeName, typeName, impl.curShellProcEnv.ProcEnv.NamedGraph.Model))
{
impl.errOut.WriteLine(valTypeName + " is not the same type as/a subtype of " + typeName + ".");
return(null);
}
return(val);
}
}
/// <summary>
/// Returns the types to which the operands must be casted to,
/// assuming an external type equality or ordering operator.
/// Returns "" if the type can only be determined at runtime.
/// Returns "-" in case of a type error and/or if no operator working on external types can be applied.
/// </summary>
private static string BalanceExternalType(string left, string right, IGraphModel model)
{
if (left == right)
{
return(left);
}
if (left == "" || right == "")
{
return("");
}
if (TypesHelper.IsSameOrSubtype(left, right, model) && TypesHelper.IsExternalTypeIncludingObjectType(right, model))
{
return(right);
}
if (TypesHelper.IsSameOrSubtype(right, left, model) && TypesHelper.IsExternalTypeIncludingObjectType(left, model))
{
return(left);
}
return("-");
}
