// CS8075: An expression tree cannot contain a collection initializer with extension method // Line: 12 using System; using System.Collections.Generic; using System.Linq.Expressions; class Program { static void Main() { Expression<Func<Stack<int>>> e = () => new Stack<int> { 42 }; } } static class X { public static void Add<T>(this Stack<T> s, T value) => s.Push (value); }