private static FSharpChoice <string, Errors> Mandatory(string s)
{
return(FSharpChoice.Validator <string>(x => !string.IsNullOrEmpty(x), "Mandatory field")(s));
//if (string.IsNullOrEmpty(s))
// return FSharpChoice.Error<string>("Mandatory field");
//return FSharpChoice.Ok(s);
}
static FSharpChoice <T, Errors> NotEqual <T>(T value, T other, string err)
{
return(FSharpChoice.Validator <T>(v => !Equals(v, other), err)(value));
}
static FSharpChoice <T, Errors> NonNull <T>(T value, string err) where T : class
{
return(FSharpChoice.Validator <T>(x => x != null, err)(value));
}