EdmFunction must be qualified with model name?

Book "Johnson Glenn - Accessing Data with Microsoft .NET Framework 4 - 2011" contains example of custom function, and call of function:

gv.DataSource = (... select new { ... , ModelDefinedFunctions.Detail(..)});

But on CD in practice tests with that book:

var instructors = from p in context.People
                  wh开发者_JS百科ere YearsSince((DateTime)p.HireDate) > 10
                  select p;

and explanation: You must refer to the custom function using the method name. The method name must not be qualified with the model name. The method requires a DateTime parameter and this must be included.

Don't have VS now, what is the right way?

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ModelDefinedFunctions is the name of the class where the method Detail is defined. The two approaches are identical. There is no qualifier for the model name.