Add Some Yoda to your linq

yoda.cs

using System;
using System.Collections.Generic;
using System.Linq;

namespace Dagobah.System
{
    public static class Yoda
    {
        public static bool IHave<T>(this IEnumerable<T> source, T value)
        {
            return source.Contains(value);
        }

        public static bool IHave<T>(this IEnumerable<T> source, T value, IEqualityComparer<T> comparer)
        {
            return source.Contains(value, comparer);
        }

        public static bool YouMust<T>(this IEnumerable<T> source, Func<T,bool> predicate)
        {
            return source.All(predicate);
        }

        public static T InThisOne<T>(this IEnumerable<T> source)
        {
            return source.FirstOrDefault();
        }

        public static T InThisOne<T>(this IEnumerable<T> source, Func<T, bool> predicate)
        {
            return source.FirstOrDefault(predicate);
        }

        public static IEnumerable<TResult> YouBe<T,TResult>(this IEnumerable<T> source)
        {
            return source.Cast<TResult>();
        }
    }
}

// usage:

using System.Linq;
using Dagobah.System;

namespace ConsoleApplication
{
    class Program
    {
        static void Main(string[] args)
        {
           int[] numbers = { 5, 4, 1, 3, 9, 8, 6, 7, 2, 0 };
           var t =  numbers
                   .Select(x => x * 2)
                   .YouMust(x => x < 7); // <-- AWESOME!!!
        }
    }
}