LangExtOptBiIterFail

Sample solution showing issue with Language-Ext package and its Option<>.BiIter() method causing a ValueIsNoneException. See issue 299 on project home.

Steps

1. Restore packages
2. Run from Visual Studio or command line
3. Press a key to actually start processing

See generated exception, wrapped in an AggregateException due to .Wait():

Type:

LanguageExt.ValueIsNoneException

Message:

Value is none.

Stacktrace:

at LanguageExt.OptionData`1.get_Value()
at LanguageExt.Option`1.get_Value()
at LanguageExt.ClassInstances.MOption`1.BiFold[S](Option`1 ma, S state, Func`3 fa, Func`3 fb)
at LanguageExt.TypeClass.biFold[FOLD,F,A,B,S](F foldable, S state, Func`3 fa, Func`3 fb)
at LanguageExt.TypeClass.biIter[FOLD,F,A,B](F foldable, Action`1 fa, Action`1 fb)
at LanguageExt.Option`1.BiIter(Action`1 Some, Action None)
at LangExtOptBiIterFail.Program.<ValidateAsync>d__2.MoveNext() in [...]\Program.cs:line 30