Func

Func.cs

using System;
using System.Linq;

namespace Kiln.Utils
{
    public static class Func
    {
        public static Func<T, bool> Not<T>(Func<T, bool> predicate)
        {
            return o => !predicate(o);
        }

        public static Func<T, bool> Or<T>(params Func<T, bool>[] clauses)
        {
            return o => clauses.Any(c => c(o));
        }
    }
}

FuncTest.cs

using Kiln.Utils;
using Microsoft.VisualStudio.TestTools.UnitTesting;

namespace Kiln.Tests
{
    [TestClass]
    public class FuncTest
    {
        [TestMethod]
        public void TestNot()
        {
            Assert.IsTrue(Func.Not<string>(string.IsNullOrEmpty)("a"));
            Assert.IsFalse(Func.Not<string>(string.IsNullOrEmpty)(""));
        }

        [TestMethod]
        public void TestOr()
        {
            var f = Func.Or(string.IsNullOrEmpty, (string s) => s == "a");
            Assert.IsTrue(f(null));
            Assert.IsTrue(f(""));
            Assert.IsTrue(f("a"));
            Assert.IsFalse(f("b"));
        }
    }
}