C/C++LI Lambda selector for LINQ static method

I have this in C/C++LI (Visual Studio 2012)

Enumerable::Max((IEnumerable^) Foos, [](IFoo^ f){return f->Id;});

but it results in this error:

No instance of overloaded function “System::Linq::Enumerable::Max”
matches argument list

It frustrates me because there is nothing wrong with the lambda. Do I need to cast it to the Func somehow?

Solution:

The C/C++ LI compiler does not support C++11 lambda expressions, they cannot be converted to delegate objects. While .NET had a big head start, support for managed lambdas was never added, and certainly never will be.

You need a delegate object with a helper function that returns IFoo->id that looks like this:

int returnId(IFoo^ obj) { return obj->Id; }... int max = Enumerable::Max((IEnumerable^) Foos, gcnew Func(returnId));

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C/C++LI Lambda selector for LINQ static method

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