Issue when opening a new workbook during a function call

[jwilder123]

Steps to reproduce:

1. =Test(TODAY())
2. Click Enter
3. Within the 1 second wait, click Ctrl + N to launch a new workbook

The results will not be returned. Furthermore, any calls on new workbooks to '=Test(TODAY())' will immediately return 'Hello' (ie: not recalling the function, simply returning the cached result)

`
using ExcelDna.Integration;
using ExcelDna.Registration;

namespace DNABug
{
public class Class1
{
public partial class Registration : IExcelAddIn
{
public void AutoOpen() => ExcelRegistration.GetExcelFunctions().ProcessAsyncRegistrations().RegisterFunctions();
public void AutoClose() { }

        [ExcelFunction(Name = "Test")]
        public static async Task<Object> Tester([ExcelArgument(Name = "p1")] object p1)
        {
            await Task.Delay(1000);
            return "Hello";
        }
    }
}

}
`

[govert]

Calling RTD-based async functions with volatile inputs is a problem, and I don't have a good 'default' solution for this yet.

Some options:

• Make your own "TODAY.NV()" function that is not volatile.
• Cache the async result for a short time (a few seconds or minutes) and return directly from the cache. This would need some re-engineering of the function instead of using the default Task-processing.

It's certainly a problem and needs more thought but is a consequence of the Excel-DNA approach to implementing async functions. Not simple . . .

[jwilder123]

Thanks so much! And thanks for all your efforts on this project! Any chance you can point me to an example of the second approach?