Func<T, bool> func = expression.Compile();
Predicate<T> pred = t => func(t);
Edit: per the comments we have a better answer for the second line:
Predicate<T> pred = func.Invoke;
Func<T, bool> func = expression.Compile();
Predicate<T> pred = t => func(t);
Edit: per the comments we have a better answer for the second line:
Predicate<T> pred = func.Invoke;