2010-05-25 Jb Evain <jbevain@novell.com>

[mcs.git] / class / System.Core / System.Linq / Queryable.cs

//
// Queryable.cs
//
// Authors:
//  Marek Safar (marek.safar@gmail.com)
//  Alejandro Serrano "Serras" (trupill@yahoo.es)
//  Jb Evain (jbevain@novell.com)
//  Andreas Noever (andreas.noever@gmail.com)
//
// Copyright (C) 2008 Novell, Inc (http://www.novell.com)
//
// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
//
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//

using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq.Expressions;
using System.Reflection;
using System.Linq;

namespace System.Linq {

        public static class Queryable {

                static MethodInfo MakeGeneric (MethodBase method, params Type [] parameters)
                {
                        return ((MethodInfo) method).MakeGenericMethod (parameters);
                }

                static Expression StaticCall (MethodInfo method, params Expression [] expressions)
                {
                        return Expression.Call (null, method, expressions);
                }

                static TRet Execute<TRet, TSource> (this IQueryable<TSource> source, MethodBase current)
                {
                        return source.Provider.Execute<TRet> (
                                StaticCall (
                                        MakeGeneric (current, typeof (TSource)),
                                        source.Expression));
                }

                #region Aggregate

                public static TSource Aggregate<TSource> (this IQueryable<TSource> source, Expression<Func<TSource, TSource, TSource>> func)
                {
                        Check.SourceAndFunc (source, func);
                        return source.Provider.Execute<TSource> (
                        StaticCall (
                                MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                source.Expression,
                                Expression.Quote (func)));
                }

                public static TAccumulate Aggregate<TSource, TAccumulate> (this IQueryable<TSource> source, TAccumulate seed, Expression<Func<TAccumulate, TSource, TAccumulate>> func)
                {
                        Check.SourceAndFunc (source, func);
                        return source.Provider.Execute<TAccumulate> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource), typeof (TAccumulate)),
                                        source.Expression,
                                        Expression.Constant (seed),
                                        Expression.Quote (func)));
                }

                public static TResult Aggregate<TSource, TAccumulate, TResult> (this IQueryable<TSource> source, TAccumulate seed, Expression<Func<TAccumulate, TSource, TAccumulate>> func, Expression<Func<TAccumulate, TResult>> selector)
                {
                        Check.SourceAndFuncAndSelector (source, func, selector);
                        return source.Provider.Execute<TResult> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource), typeof (TAccumulate), typeof (TResult)),
                                        source.Expression,
                                        Expression.Constant (seed),
                                        Expression.Quote (func),
                                        Expression.Quote (selector)));
                }

                #endregion

                #region All

                public static bool All<TSource> (this IQueryable<TSource> source, Expression<Func<TSource, bool>> predicate)
                {
                        Check.SourceAndPredicate (source, predicate);

                        return source.Provider.Execute<bool> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (predicate)));
                }

                #endregion

                #region Any

                public static bool Any<TSource> (this IQueryable<TSource> source)
                {
                        Check.Source (source);

                        return source.Provider.Execute<bool> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression));
                }

                public static bool Any<TSource> (this IQueryable<TSource> source, Expression<Func<TSource, bool>> predicate)
                {
                        Check.SourceAndPredicate (source, predicate);

                        return source.Provider.Execute<bool> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (predicate)));
                }

                #endregion

                #region AsQueryable

                public static IQueryable<TElement> AsQueryable<TElement> (this IEnumerable<TElement> source)
                {
                        if (source == null)
                                throw new ArgumentNullException ("source");

                        var queryable = source as IQueryable<TElement>;
                        if (queryable != null)
                                return queryable;

                        return new QueryableEnumerable<TElement> (source);
                }

                public static IQueryable AsQueryable (this IEnumerable source)
                {
                        if (source == null)
                                throw new ArgumentNullException ("source");

                        var queryable = source as IQueryable;
                        if (queryable != null)
                                return queryable;

                        var type = source.GetType ();

                        if (!type.IsGenericImplementationOf (typeof (IEnumerable<>)))
                                throw new ArgumentException ("source is not IEnumerable<>");

                        return (IQueryable) Activator.CreateInstance (
                                typeof (QueryableEnumerable<>).MakeGenericType (type.GetFirstGenericArgument ()), source);
                }

                #endregion

                #region Average

                public static double Average (this IQueryable<int> source)
                {
                        Check.Source (source);

                        return source.Provider.Execute<double>(
                                StaticCall (
                                        (MethodInfo) MethodBase.GetCurrentMethod (),
                                        source.Expression));
                }

                public static double? Average(this IQueryable<int?> source)
                {
                        Check.Source (source);

                        return source.Provider.Execute<double?>(
                                StaticCall (
                                        (MethodInfo) MethodBase.GetCurrentMethod (),
                                        source.Expression));
                }

                public static double Average(this IQueryable<long> source)
                {
                        Check.Source (source);

                        return source.Provider.Execute<double>(
                                StaticCall (
                                        (MethodInfo) MethodBase.GetCurrentMethod (),
                                        source.Expression));
                }

                public static double? Average(this IQueryable<long?> source)
                {
                        Check.Source (source);

                        return source.Provider.Execute<double?>(
                                StaticCall (
                                        (MethodInfo) MethodBase.GetCurrentMethod (),
                                        source.Expression));
                }

                public static float Average(this IQueryable<float> source)
                {
                        Check.Source (source);

                        return source.Provider.Execute<float>(
                                StaticCall (
                                        (MethodInfo) MethodBase.GetCurrentMethod (),
                                        source.Expression));
                }

                public static float? Average(this IQueryable<float?> source)
                {
                        Check.Source (source);

                        return source.Provider.Execute<float?>(
                                StaticCall (
                                        (MethodInfo) MethodBase.GetCurrentMethod (),
                                        source.Expression));
                }

                public static double Average (this IQueryable<double> source)
                {
                        Check.Source (source);

                        return source.Provider.Execute<double> (
                                StaticCall (
                                (MethodInfo) MethodBase.GetCurrentMethod (),
                                        source.Expression));
                }

                public static double? Average (this IQueryable<double?> source)
                {
                        Check.Source (source);

                        return source.Provider.Execute<double?> (
                                StaticCall (
                                (MethodInfo) MethodBase.GetCurrentMethod (),
                                        source.Expression));
                }

                public static decimal Average(this IQueryable<decimal> source)
                {
                        Check.Source (source);

                        return source.Provider.Execute<decimal>(
                                StaticCall (
                                (MethodInfo) MethodBase.GetCurrentMethod (),
                                        source.Expression));
                }

                public static decimal? Average(this IQueryable<decimal?> source)
                {
                        Check.Source (source);

                        return source.Provider.Execute<decimal?>(
                                StaticCall (
                                        (MethodInfo) MethodBase.GetCurrentMethod (),
                                        source.Expression));
                }

                public static double Average<TSource>(this IQueryable<TSource> source, Expression<Func<TSource, int>> selector)
                {
                        Check.SourceAndSelector (source, selector);

                        return source.Provider.Execute<double>(
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (selector)));
                }

                public static double? Average<TSource>(this IQueryable<TSource> source, Expression<Func<TSource, int?>> selector)
                {
                        Check.SourceAndSelector (source, selector);

                        return source.Provider.Execute<double?>(
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (selector)));
                }

                public static double Average<TSource>(this IQueryable<TSource> source, Expression<Func<TSource, long>> selector)
                {
                        Check.SourceAndSelector (source, selector);

                        return source.Provider.Execute<double>(
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (selector)));
                }

                public static double? Average<TSource>(this IQueryable<TSource> source, Expression<Func<TSource, long?>> selector)
                {
                        Check.SourceAndSelector (source, selector);

                        return source.Provider.Execute<double?>(
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (selector)));
                }

                public static float Average<TSource>(this IQueryable<TSource> source, Expression<Func<TSource, float>> selector)
                {
                        Check.SourceAndSelector (source, selector);

                        return source.Provider.Execute<float>(
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (selector)));
                }

                public static float? Average<TSource>(this IQueryable<TSource> source, Expression<Func<TSource, float?>> selector)
                {
                        Check.SourceAndSelector (source, selector);

                        return source.Provider.Execute<float?>(
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (selector)));
                }

                public static double Average<TSource> (this IQueryable<TSource> source, Expression<Func<TSource, double>> selector)
                {
                        Check.SourceAndSelector (source, selector);

                        return source.Provider.Execute<double> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (selector)));
                }

                public static double? Average<TSource> (this IQueryable<TSource> source, Expression<Func<TSource, double?>> selector)
                {
                        Check.SourceAndSelector (source, selector);

                        return source.Provider.Execute<double?> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (selector)));
                }

                public static decimal Average<TSource>(this IQueryable<TSource> source, Expression<Func<TSource, decimal>> selector)
                {
                        Check.SourceAndSelector (source, selector);

                        return source.Provider.Execute<decimal>(
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (selector)));
                }

                public static decimal? Average<TSource>(this IQueryable<TSource> source, Expression<Func<TSource, decimal?>> selector)
                {
                        Check.SourceAndSelector (source, selector);

                        return source.Provider.Execute<decimal?>(
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (selector)));
                }

                #endregion

                #region Cast

                public static IQueryable<TResult> Cast<TResult> (this IQueryable source)
                {
                        Check.Source (source);

                        return (IQueryable<TResult>) source.Provider.CreateQuery (
                                StaticCall (MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TResult)),
                                        source.Expression));
                }

                #endregion

                #region Concat

                public static IQueryable<TSource> Concat<TSource> (this IQueryable<TSource> source1, IEnumerable<TSource> source2)
                {
                        Check.Source1AndSource2 (source1, source2);

                        return source1.Provider.CreateQuery<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source1.Expression,
                                        Expression.Constant (source2)));
                }

                #endregion

                #region Contains

                public static bool Contains<TSource> (this IQueryable<TSource> source, TSource item)
                {
                        Check.Source (source);

                        return source.Provider.Execute<bool> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Constant (item)));
                }

                public static bool Contains<TSource> (this IQueryable<TSource> source, TSource item, IEqualityComparer<TSource> comparer)
                {
                        Check.Source (source);

                        return source.Provider.Execute<bool> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Constant (item),
                                        Expression.Constant (comparer)));
                }

                #endregion

                #region Count

                public static int Count<TSource> (this IQueryable<TSource> source)
                {
                        Check.Source (source);

                        return source.Execute<int, TSource> (MethodBase.GetCurrentMethod ());
                }

                public static int Count<TSource> (this IQueryable<TSource> source, Expression<Func<TSource, bool>> predicate)
                {
                        Check.SourceAndPredicate (source, predicate);

                        return source.Provider.Execute<int> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (predicate)));
                }

                #endregion

                #region DefaultIfEmpty

                public static IQueryable<TSource> DefaultIfEmpty<TSource> (this IQueryable<TSource> source)
                {
                        Check.Source (source);

                        return source.Provider.CreateQuery<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression));
                }

                public static IQueryable<TSource> DefaultIfEmpty<TSource> (this IQueryable<TSource> source, TSource defaultValue)
                {
                        Check.Source (source);

                        return source.Provider.CreateQuery<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Constant (defaultValue)));
                }

                #endregion

                #region Distinct

                public static IQueryable<TSource> Distinct<TSource> (this IQueryable<TSource> source)
                {
                        Check.Source (source);

                        return source.Provider.CreateQuery<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression));
                }

                public static IQueryable<TSource> Distinct<TSource> (this IQueryable<TSource> source, IEqualityComparer<TSource> comparer)
                {
                        Check.Source (source);

                        return source.Provider.CreateQuery<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Constant (comparer)));
                }

                #endregion

                #region ElementAt

                public static TSource ElementAt<TSource> (this IQueryable<TSource> source, int index)
                {
                        Check.Source (source);

                        return source.Provider.Execute<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Constant (index)));
                }

                #endregion

                #region ElementAtOrDefault

                public static TSource ElementAtOrDefault<TSource> (this IQueryable<TSource> source, int index)
                {
                        Check.Source (source);

                        return source.Provider.Execute<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Constant (index)));
                }

                #endregion

                #region Except

                public static IQueryable<TSource> Except<TSource> (this IQueryable<TSource> source1, IEnumerable<TSource> source2)
                {
                        Check.Source1AndSource2 (source1, source2);

                        return source1.Provider.CreateQuery<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source1.Expression,
                                        Expression.Constant (source2)));
                }

                public static IQueryable<TSource> Except<TSource> (this IQueryable<TSource> source1, IEnumerable<TSource> source2, IEqualityComparer<TSource> comparer)
                {
                        Check.Source1AndSource2 (source1, source2);

                        return source1.Provider.CreateQuery<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source1.Expression,
                                        Expression.Constant (source2),
                                        Expression.Constant (comparer)));
                }

                #endregion

                #region First

                public static TSource First<TSource> (this IQueryable<TSource> source)
                {
                        Check.Source (source);

                        return source.Provider.Execute<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression));
                }

                public static TSource First<TSource> (this IQueryable<TSource> source, Expression<Func<TSource, bool>> predicate)
                {
                        Check.SourceAndPredicate (source, predicate);

                        return source.Provider.Execute<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (predicate)));
                }

                #endregion

                #region FirstOrDefault

                public static TSource FirstOrDefault<TSource> (this IQueryable<TSource> source)
                {
                        Check.Source (source);

                        return source.Provider.Execute<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression));
                }

                public static TSource FirstOrDefault<TSource> (this IQueryable<TSource> source, Expression<Func<TSource, bool>> predicate)
                {
                        Check.SourceAndPredicate (source, predicate);

                        return source.Provider.Execute<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (predicate)));
                }

                #endregion

                #region GroupBy

                public static IQueryable<IGrouping<TKey, TSource>> GroupBy<TSource, TKey> (this IQueryable<TSource> source, Expression<Func<TSource, TKey>> keySelector)
                {
                        Check.SourceAndKeySelector (source, keySelector);

                        return source.Provider.CreateQuery<IGrouping<TKey, TSource>> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource), typeof (TKey)),
                                        source.Expression,
                                        Expression.Quote (keySelector)));
                }
                public static IQueryable<IGrouping<TKey, TSource>> GroupBy<TSource, TKey> (this IQueryable<TSource> source, Expression<Func<TSource, TKey>> keySelector, IEqualityComparer<TKey> comparer)
                {
                        Check.SourceAndKeySelector (source, keySelector);

                        return source.Provider.CreateQuery<IGrouping<TKey, TSource>> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource), typeof (TKey)),
                                        source.Expression,
                                        Expression.Quote (keySelector),
                                        Expression.Constant (comparer)));
                }
                public static IQueryable<IGrouping<TKey, TElement>> GroupBy<TSource, TKey, TElement> (this IQueryable<TSource> source, Expression<Func<TSource, TKey>> keySelector, Expression<Func<TSource, TElement>> elementSelector)
                {
                        Check.SourceAndKeyElementSelectors (source, keySelector, elementSelector);

                        return source.Provider.CreateQuery<IGrouping<TKey, TElement>>(
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource), typeof (TKey), typeof (TElement)),
                                        source.Expression,
                                        Expression.Quote (keySelector),
                                        Expression.Quote (elementSelector)));
                }
                public static IQueryable<TResult> GroupBy<TSource, TKey, TResult> (this IQueryable<TSource> source, Expression<Func<TSource, TKey>> keySelector, Expression<Func<TKey, IEnumerable<TSource>, TResult>> resultSelector)
                {
                        Check.SourceAndKeyResultSelectors (source, keySelector, resultSelector);

                        return source.Provider.CreateQuery<TResult> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource), typeof (TKey), typeof (TResult)),
                                        source.Expression,
                                        Expression.Quote (keySelector),
                                        Expression.Quote (resultSelector)));
                }
                public static IQueryable<IGrouping<TKey, TElement>> GroupBy<TSource, TKey, TElement> (this IQueryable<TSource> source, Expression<Func<TSource, TKey>> keySelector, Expression<Func<TSource, TElement>> elementSelector, IEqualityComparer<TKey> comparer)
                {
                        Check.SourceAndKeyElementSelectors (source, keySelector, elementSelector);

                        return source.Provider.CreateQuery<IGrouping<TKey, TElement>> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource), typeof (TKey), typeof (TElement)),
                                        source.Expression,
                                        Expression.Quote (keySelector),
                                        Expression.Quote (elementSelector),
                                        Expression.Constant (comparer)));
                }
                public static IQueryable<TResult> GroupBy<TSource, TKey, TElement, TResult> (this IQueryable<TSource> source, Expression<Func<TSource, TKey>> keySelector, Expression<Func<TSource, TElement>> elementSelector, Expression<Func<TKey, IEnumerable<TElement>, TResult>> resultSelector)
                {
                        Check.GroupBySelectors (source, keySelector, elementSelector, resultSelector);

                        return source.Provider.CreateQuery<TResult> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource), typeof (TKey), typeof (TElement), typeof (TResult)),
                                        source.Expression,
                                        Expression.Quote (keySelector),
                                        Expression.Quote (elementSelector),
                                        Expression.Quote (resultSelector)));
                }

                public static IQueryable<TResult> GroupBy<TSource, TKey, TResult> (this IQueryable<TSource> source, Expression<Func<TSource, TKey>> keySelector, Expression<Func<TKey, IEnumerable<TSource>, TResult>> resultSelector, IEqualityComparer<TKey> comparer)
                {
                        Check.SourceAndKeyResultSelectors (source, keySelector, resultSelector);

                        return source.Provider.CreateQuery<TResult> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource), typeof (TKey), typeof (TResult)),
                                        source.Expression,
                                        Expression.Quote (keySelector),
                                        Expression.Quote (resultSelector),
                                        Expression.Constant (comparer)));
                }
                public static IQueryable<TResult> GroupBy<TSource, TKey, TElement, TResult> (this IQueryable<TSource> source, Expression<Func<TSource, TKey>> keySelector, Expression<Func<TSource, TElement>> elementSelector, Expression<Func<TKey, IEnumerable<TElement>, TResult>> resultSelector, IEqualityComparer<TKey> comparer)
                {
                        Check.GroupBySelectors (source, keySelector, elementSelector, resultSelector);

                        return source.Provider.CreateQuery<TResult> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource), typeof (TKey), typeof (TElement), typeof (TResult)),
                                        source.Expression,
                                        Expression.Quote (keySelector),
                                        Expression.Quote (elementSelector),
                                        Expression.Quote (resultSelector),
                                        Expression.Constant (comparer)));
                }
                #endregion

                #region GroupJoin

                public static IQueryable<TResult> GroupJoin<TOuter, TInner, TKey, TResult> (this IQueryable<TOuter> outer, IEnumerable<TInner> inner, Expression<Func<TOuter, TKey>> outerKeySelector, Expression<Func<TInner, TKey>> innerKeySelector, Expression<Func<TOuter, IEnumerable<TInner>, TResult>> resultSelector)
                {
                        if (outer == null)
                                throw new ArgumentNullException ("outer");
                        if (inner == null)
                                throw new ArgumentNullException ("inner");
                        if (outerKeySelector == null)
                                throw new ArgumentNullException ("outerKeySelector");
                        if (innerKeySelector == null)
                                throw new ArgumentNullException ("innerKeySelector");
                        if (resultSelector == null)
                                throw new ArgumentNullException ("resultSelector");

                        return outer.Provider.CreateQuery<TResult> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TOuter), typeof (TInner), typeof (TKey), typeof (TResult)),
                                        outer.Expression,
                                        Expression.Constant (inner),
                                        Expression.Quote (outerKeySelector),
                                        Expression.Quote (innerKeySelector),
                                        Expression.Quote (resultSelector)));
                }

                public static IQueryable<TResult> GroupJoin<TOuter, TInner, TKey, TResult> (this IQueryable<TOuter> outer, IEnumerable<TInner> inner, Expression<Func<TOuter, TKey>> outerKeySelector, Expression<Func<TInner, TKey>> innerKeySelector, Expression<Func<TOuter, IEnumerable<TInner>, TResult>> resultSelector, IEqualityComparer<TKey> comparer)
                {
                        if (outer == null)
                                throw new ArgumentNullException ("outer");
                        if (inner == null)
                                throw new ArgumentNullException ("inner");
                        if (outerKeySelector == null)
                                throw new ArgumentNullException ("outerKeySelector");
                        if (innerKeySelector == null)
                                throw new ArgumentNullException ("innerKeySelector");
                        if (resultSelector == null)
                                throw new ArgumentNullException ("resultSelector");

                        return outer.Provider.CreateQuery<TResult> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TOuter), typeof (TInner), typeof (TKey), typeof (TResult)),
                                        outer.Expression,
                                        Expression.Constant (inner),
                                        Expression.Quote (outerKeySelector),
                                        Expression.Quote (innerKeySelector),
                                        Expression.Quote (resultSelector),
                                        Expression.Constant (comparer)));
                }

                #endregion

                #region Intersect

                public static IQueryable<TSource> Intersect<TSource> (this IQueryable<TSource> source1, IEnumerable<TSource> source2)
                {
                        Check.Source1AndSource2 (source1, source2);

                        return source1.Provider.CreateQuery<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source1.Expression,
                                        Expression.Constant (source2)));
                }

                public static IQueryable<TSource> Intersect<TSource> (this IQueryable<TSource> source1, IEnumerable<TSource> source2, IEqualityComparer<TSource> comparer)
                {
                        Check.Source1AndSource2 (source1, source2);

                        return source1.Provider.CreateQuery<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source1.Expression,
                                        Expression.Constant (source2),
                                        Expression.Constant (comparer)));
                }

                #endregion

                #region Join

                public static IQueryable<TResult> Join<TOuter, TInner, TKey, TResult> (this IQueryable<TOuter> outer, IEnumerable<TInner> inner, Expression<Func<TOuter, TKey>> outerKeySelector, Expression<Func<TInner, TKey>> innerKeySelector, Expression<Func<TOuter, TInner, TResult>> resultSelector)
                {
                        Check.JoinSelectors (outer, inner, outerKeySelector, innerKeySelector, resultSelector);

                        return outer.Provider.CreateQuery<TResult> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TOuter), typeof (TInner), typeof (TKey), typeof (TResult)),
                                        outer.Expression,
                                        Expression.Constant (inner),
                                        Expression.Quote (outerKeySelector),
                                        Expression.Quote (innerKeySelector),
                                        Expression.Quote (resultSelector)));
                }

                public static IQueryable<TResult> Join<TOuter, TInner, TKey, TResult> (this IQueryable<TOuter> outer, IEnumerable<TInner> inner, Expression<Func<TOuter, TKey>> outerKeySelector, Expression<Func<TInner, TKey>> innerKeySelector, Expression<Func<TOuter, TInner, TResult>> resultSelector, IEqualityComparer<TKey> comparer)
                {
                        Check.JoinSelectors (outer, inner, outerKeySelector, innerKeySelector, resultSelector);

                        return outer.Provider.CreateQuery<TResult> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TOuter), typeof (TInner), typeof (TKey), typeof (TResult)),
                                        outer.Expression,
                                        Expression.Constant (inner),
                                        Expression.Quote (outerKeySelector),
                                        Expression.Quote (innerKeySelector),
                                        Expression.Quote (resultSelector),
                                        Expression.Constant (comparer)));
                }


                #endregion

                #region Last

                public static TSource Last<TSource> (this IQueryable<TSource> source)
                {
                        Check.Source (source);

                        return source.Provider.Execute<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression));
                }

                public static TSource Last<TSource> (this IQueryable<TSource> source, Expression<Func<TSource, bool>> predicate)
                {
                        Check.SourceAndPredicate (source, predicate);

                        return source.Provider.Execute<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (predicate)));
                }

                #endregion

                #region LastOrDefault

                public static TSource LastOrDefault<TSource> (this IQueryable<TSource> source)
                {
                        Check.Source (source);

                        return source.Provider.Execute<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression));
                }

                public static TSource LastOrDefault<TSource> (this IQueryable<TSource> source, Expression<Func<TSource, bool>> predicate)
                {
                        Check.SourceAndPredicate (source, predicate);

                        return source.Provider.Execute<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (predicate)));
                }

                #endregion

                #region LongCount

                public static long LongCount<TSource> (this IQueryable<TSource> source)
                {
                        Check.Source (source);

                        return source.Execute<long, TSource> (MethodBase.GetCurrentMethod ());
                }

                public static long LongCount<TSource> (this IQueryable<TSource> source, Expression<Func<TSource, bool>> predicate)
                {
                        Check.SourceAndPredicate (source, predicate);

                        return source.Provider.Execute<long> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (predicate)));
                }

                #endregion

                #region Max

                public static TSource Max<TSource> (this IQueryable<TSource> source)
                {
                        Check.Source (source);

                        return source.Provider.Execute<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression));
                }

                public static TResult Max<TSource, TResult> (this IQueryable<TSource> source, Expression<Func<TSource, TResult>> selector)
                {
                        Check.Source (source);

                        return source.Provider.Execute<TResult> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource), typeof (TResult)),
                                        source.Expression,
                                        Expression.Quote (selector)));
                }


                #endregion

                #region Min

                public static TSource Min<TSource> (this IQueryable<TSource> source)
                {
                        Check.Source (source);

                        return source.Provider.Execute<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression));
                }

                public static TResult Min<TSource, TResult> (this IQueryable<TSource> source, Expression<Func<TSource, TResult>> selector)
                {
                        Check.SourceAndSelector (source, selector);

                        return source.Provider.Execute<TResult> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource), typeof (TResult)),
                                        source.Expression,
                                        Expression.Quote (selector)));
                }


                #endregion

                #region OfType

                public static IQueryable<TResult> OfType<TResult> (this IQueryable source)
                {
                        Check.Source (source);

                        return (IQueryable<TResult>) source.Provider.CreateQuery (
                        StaticCall (
                                MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TResult)),
                                source.Expression));
                }

                #endregion

                #region OrderBy

                public static IOrderedQueryable<TSource> OrderBy<TSource, TKey> (this IQueryable<TSource> source, Expression<Func<TSource, TKey>> keySelector)
                {
                        Check.SourceAndKeySelector (source, keySelector);

                        return (IOrderedQueryable<TSource>) source.Provider.CreateQuery<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource), typeof (TKey)),
                                        source.Expression,
                                        Expression.Quote (keySelector)));
                }

                public static IOrderedQueryable<TSource> OrderBy<TSource, TKey> (this IQueryable<TSource> source, Expression<Func<TSource, TKey>> keySelector, IComparer<TKey> comparer)
                {
                        Check.SourceAndKeySelector (source, keySelector);

                        return (IOrderedQueryable<TSource>) source.Provider.CreateQuery<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource), typeof (TKey)),
                                        source.Expression,
                                        Expression.Quote (keySelector),
                                        Expression.Constant (comparer)));
                }

                #endregion

                #region OrderByDescending

                public static IOrderedQueryable<TSource> OrderByDescending<TSource, TKey> (this IQueryable<TSource> source, Expression<Func<TSource, TKey>> keySelector)
                {
                        Check.SourceAndKeySelector (source, keySelector);

                        return (IOrderedQueryable<TSource>) source.Provider.CreateQuery<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource), typeof (TKey)),
                                        source.Expression,
                                        Expression.Quote (keySelector)));
                }

                public static IOrderedQueryable<TSource> OrderByDescending<TSource, TKey> (this IQueryable<TSource> source, Expression<Func<TSource, TKey>> keySelector, IComparer<TKey> comparer)
                {
                        Check.SourceAndKeySelector (source, keySelector);

                        return (IOrderedQueryable<TSource>) source.Provider.CreateQuery<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource), typeof (TKey)),
                                        source.Expression,
                                        Expression.Quote (keySelector),
                                        Expression.Constant (comparer)));
                }

                #endregion

                #region Reverse

                public static IQueryable<TSource> Reverse<TSource> (this IQueryable<TSource> source)
                {
                        Check.Source (source);

                        return source.Provider.CreateQuery<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression));
                }

                #endregion

                #region Select

                public static IQueryable<TResult> Select<TSource, TResult> (this IQueryable<TSource> source, Expression<Func<TSource, TResult>> selector)
                {
                        Check.SourceAndSelector (source, selector);

                        return source.Provider.CreateQuery<TResult> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource), typeof (TResult)),
                                        source.Expression,
                                        Expression.Quote (selector)));
                }

                public static IQueryable<TResult> Select<TSource, TResult> (this IQueryable<TSource> source, Expression<Func<TSource, int, TResult>> selector)
                {
                        Check.SourceAndSelector (source, selector);

                        return source.Provider.CreateQuery<TResult> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource), typeof (TResult)),
                                        source.Expression,
                                        Expression.Quote (selector)));
                }

                #endregion

                #region SelectMany

                public static IQueryable<TResult> SelectMany<TSource, TResult> (this IQueryable<TSource> source, Expression<Func<TSource, IEnumerable<TResult>>> selector)
                {
                        Check.SourceAndSelector (source, selector);

                        return source.Provider.CreateQuery<TResult> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource), typeof (TResult)),
                                        source.Expression,
                                        Expression.Quote (selector)));
                }

                public static IQueryable<TResult> SelectMany<TSource, TResult> (this IQueryable<TSource> source, Expression<Func<TSource, int, IEnumerable<TResult>>> selector)
                {
                        Check.SourceAndSelector (source, selector);

                        return source.Provider.CreateQuery<TResult> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource), typeof (TResult)),
                                        source.Expression,
                                        Expression.Quote (selector)));
                }

                public static IQueryable<TResult> SelectMany<TSource, TCollection, TResult> (this IQueryable<TSource> source, Expression<Func<TSource, int, IEnumerable<TCollection>>> collectionSelector, Expression<Func<TSource, TCollection, TResult>> resultSelector)
                {
                        Check.SourceAndCollectionSelectorAndResultSelector (source, collectionSelector, resultSelector);

                        return source.Provider.CreateQuery<TResult> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource), typeof (TCollection), typeof (TResult)),
                                        source.Expression,
                                        Expression.Quote (collectionSelector),
                                        Expression.Quote (resultSelector)));
                }

                public static IQueryable<TResult> SelectMany<TSource, TCollection, TResult> (this IQueryable<TSource> source, Expression<Func<TSource, IEnumerable<TCollection>>> collectionSelector, Expression<Func<TSource, TCollection, TResult>> resultSelector)
                {
                        Check.SourceAndCollectionSelectorAndResultSelector (source, collectionSelector, resultSelector);

                        return source.Provider.CreateQuery<TResult> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource), typeof (TCollection), typeof (TResult)),
                                        source.Expression,
                                        Expression.Quote (collectionSelector),
                                        Expression.Quote (resultSelector)));
                }

                #endregion

                #region SequenceEqual

                public static bool SequenceEqual<TSource> (this IQueryable<TSource> source1, IEnumerable<TSource> source2)
                {
                        Check.Source1AndSource2 (source1, source2);

                        return source1.Provider.Execute<bool> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source1.Expression,
                                        Expression.Constant (source2)));
                }

                public static bool SequenceEqual<TSource> (this IQueryable<TSource> source1, IEnumerable<TSource> source2, IEqualityComparer<TSource> comparer)
                {
                        Check.Source1AndSource2 (source1, source2);

                        return source1.Provider.Execute<bool> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source1.Expression,
                                        Expression.Constant (source2),
                                        Expression.Constant (comparer)));
                }

                #endregion

                #region Single

                public static TSource Single<TSource> (this IQueryable<TSource> source)
                {
                        Check.Source (source);

                        return source.Provider.Execute<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression));
                }

                public static TSource Single<TSource> (this IQueryable<TSource> source, Expression<Func<TSource, bool>> predicate)
                {
                        Check.SourceAndPredicate (source, predicate);

                        return source.Provider.Execute<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (predicate)));
                }

                #endregion

                #region SingleOrDefault

                public static TSource SingleOrDefault<TSource> (this IQueryable<TSource> source)
                {
                        Check.Source (source);

                        return source.Provider.Execute<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression));
                }

                public static TSource SingleOrDefault<TSource> (this IQueryable<TSource> source, Expression<Func<TSource, bool>> predicate)
                {
                        Check.SourceAndPredicate (source, predicate);

                        return source.Provider.Execute<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (predicate)));
                }

                #endregion

                #region Skip

                public static IQueryable<TSource> Skip<TSource> (this IQueryable<TSource> source, int count)
                {
                        Check.Source (source);

                        return source.Provider.CreateQuery<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Constant (count)));
                }

                #endregion

                #region SkipWhile

                public static IQueryable<TSource> SkipWhile<TSource> (this IQueryable<TSource> source, Expression<Func<TSource, bool>> predicate)
                {
                        Check.SourceAndPredicate (source, predicate);

                        return source.Provider.CreateQuery<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (predicate)));
                }

                public static IQueryable<TSource> SkipWhile<TSource> (this IQueryable<TSource> source, Expression<Func<TSource, int, bool>> predicate)
                {
                        Check.SourceAndPredicate (source, predicate);

                        return source.Provider.CreateQuery<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (predicate)));
                }


                #endregion

                #region Sum


                public static int Sum<TSource> (this IQueryable<TSource> source, Expression<Func<TSource, int>> selector)
                {
                        Check.SourceAndSelector (source, selector);

                        return source.Provider.Execute<int> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (selector)));
                }

                public static int? Sum<TSource> (this IQueryable<TSource> source, Expression<Func<TSource, int?>> selector)
                {
                        Check.SourceAndSelector (source, selector);

                        return source.Provider.Execute<int?> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (selector)));
                }

                public static long Sum<TSource> (this IQueryable<TSource> source, Expression<Func<TSource, long>> selector)
                {
                        Check.SourceAndSelector (source, selector);

                        return source.Provider.Execute<long> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (selector)));
                }

                public static long? Sum<TSource> (this IQueryable<TSource> source, Expression<Func<TSource, long?>> selector)
                {
                        Check.SourceAndSelector (source, selector);

                        return source.Provider.Execute<long?> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (selector)));
                }

                public static float Sum<TSource> (this IQueryable<TSource> source, Expression<Func<TSource, float>> selector)
                {
                        Check.SourceAndSelector (source, selector);

                        return source.Provider.Execute<float> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (selector)));
                }

                public static float? Sum<TSource> (this IQueryable<TSource> source, Expression<Func<TSource, float?>> selector)
                {
                        Check.SourceAndSelector (source, selector);

                        return source.Provider.Execute<float?> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (selector)));
                }

                public static double Sum<TSource> (this IQueryable<TSource> source, Expression<Func<TSource, double>> selector)
                {
                        Check.SourceAndSelector (source, selector);

                        return source.Provider.Execute<double> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (selector)));
                }

                public static double? Sum<TSource> (this IQueryable<TSource> source, Expression<Func<TSource, double?>> selector)
                {
                        Check.SourceAndSelector (source, selector);

                        return source.Provider.Execute<double?> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (selector)));
                }

                public static decimal Sum<TSource> (this IQueryable<TSource> source, Expression<Func<TSource, decimal>> selector)
                {
                        Check.SourceAndSelector (source, selector);

                        return source.Provider.Execute<decimal> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (selector)));
                }

                public static decimal? Sum<TSource> (this IQueryable<TSource> source, Expression<Func<TSource, decimal?>> selector)
                {
                        Check.SourceAndSelector (source, selector);

                        return source.Provider.Execute<decimal?> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (selector)));
                }

                public static int Sum (this IQueryable<int> source)
                {
                        Check.Source (source);

                        return source.Provider.Execute<int> (
                                StaticCall (
                                        (MethodInfo) MethodBase.GetCurrentMethod (),
                                        source.Expression));
                }

                public static int? Sum (this IQueryable<int?> source)
                {
                        Check.Source (source);

                        return source.Provider.Execute<int?> (
                                StaticCall (
                                        (MethodInfo) MethodBase.GetCurrentMethod (),
                                        source.Expression));
                }



                public static long Sum (this IQueryable<long> source)
                {
                        Check.Source (source);

                        return source.Provider.Execute<long> (
                                StaticCall (
                                        (MethodInfo) MethodBase.GetCurrentMethod (),
                                        source.Expression));
                }



                public static long? Sum (this IQueryable<long?> source)
                {
                        Check.Source (source);

                        return source.Provider.Execute<long?> (
                                StaticCall (
                                        (MethodInfo) MethodBase.GetCurrentMethod (),
                                        source.Expression));
                }

                public static float Sum (this IQueryable<float> source)
                {
                        Check.Source (source);

                        return source.Provider.Execute<float> (
                                StaticCall (
                                        (MethodInfo) MethodBase.GetCurrentMethod (),
                                        source.Expression));
                }

                public static float? Sum (this IQueryable<float?> source)
                {
                        Check.Source (source);

                        return source.Provider.Execute<float?> (
                                StaticCall (
                                        (MethodInfo) MethodBase.GetCurrentMethod (),
                                        source.Expression));
                }


                public static double Sum (this IQueryable<double> source)
                {
                        Check.Source (source);

                        return source.Provider.Execute<double> (
                                StaticCall (
                                        (MethodInfo) MethodBase.GetCurrentMethod (),
                                        source.Expression));
                }



                public static double? Sum (this IQueryable<double?> source)
                {
                        Check.Source (source);

                        return source.Provider.Execute<double?> (
                                StaticCall (
                                        (MethodInfo) MethodBase.GetCurrentMethod (),
                                        source.Expression));
                }


                public static decimal Sum (this IQueryable<decimal> source)
                {
                        Check.Source (source);

                        return source.Provider.Execute<decimal> (
                                StaticCall (
                                        (MethodInfo) MethodBase.GetCurrentMethod (),
                                        source.Expression));
                }



                public static decimal? Sum (this IQueryable<decimal?> source)
                {
                        Check.Source (source);

                        return source.Provider.Execute<decimal?> (
                                StaticCall (
                                        (MethodInfo) MethodBase.GetCurrentMethod (),
                                        source.Expression));
                }



                #endregion

                #region Take

                public static IQueryable<TSource> Take<TSource> (this IQueryable<TSource> source, int count)
                {
                        Check.Source (source);

                        return source.Provider.CreateQuery<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Constant (count)));
                }

                #endregion

                #region TakeWhile

                public static IQueryable<TSource> TakeWhile<TSource> (this IQueryable<TSource> source, Expression<Func<TSource, bool>> predicate)
                {
                        Check.SourceAndPredicate (source, predicate);

                        return source.Provider.CreateQuery<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (predicate)));
                }

                public static IQueryable<TSource> TakeWhile<TSource> (this IQueryable<TSource> source, Expression<Func<TSource, int, bool>> predicate)
                {
                        Check.SourceAndPredicate (source, predicate);

                        return source.Provider.CreateQuery<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (predicate)));
                }

                #endregion

                #region ThenBy

                public static IOrderedQueryable<TSource> ThenBy<TSource, TKey> (this IOrderedQueryable<TSource> source, Expression<Func<TSource, TKey>> keySelector)
                {
                        Check.SourceAndKeySelector (source, keySelector);

                        return (IOrderedQueryable<TSource>) source.Provider.CreateQuery (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource), typeof (TKey)),
                                        source.Expression,
                                        Expression.Quote (keySelector)));
                }

                public static IOrderedQueryable<TSource> ThenBy<TSource, TKey> (this IOrderedQueryable<TSource> source, Expression<Func<TSource, TKey>> keySelector, IComparer<TKey> comparer)
                {
                        Check.SourceAndKeySelector (source, keySelector);

                        return (IOrderedQueryable<TSource>) source.Provider.CreateQuery (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource), typeof (TKey)),
                                        source.Expression,
                                        Expression.Quote (keySelector),
                                        Expression.Constant (comparer)));
                }

                #endregion

                #region ThenByDescending

                public static IOrderedQueryable<TSource> ThenByDescending<TSource, TKey> (this IOrderedQueryable<TSource> source, Expression<Func<TSource, TKey>> keySelector)
                {
                        Check.SourceAndKeySelector (source, keySelector);

                        return (IOrderedQueryable<TSource>) source.Provider.CreateQuery (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource), typeof (TKey)),
                                        source.Expression,
                                        Expression.Quote (keySelector)));
                }

                public static IOrderedQueryable<TSource> ThenByDescending<TSource, TKey> (this IOrderedQueryable<TSource> source, Expression<Func<TSource, TKey>> keySelector, IComparer<TKey> comparer)
                {
                        Check.SourceAndKeySelector (source, keySelector);

                        return (IOrderedQueryable<TSource>) source.Provider.CreateQuery (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource), typeof (TKey)),
                                        source.Expression,
                                        Expression.Quote (keySelector),
                                        Expression.Constant (comparer)));
                }

                #endregion

                #region Union

                public static IQueryable<TSource> Union<TSource> (this IQueryable<TSource> source1, IEnumerable<TSource> source2)
                {
                        Check.Source1AndSource2 (source1, source2);

                        return source1.Provider.CreateQuery<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source1.Expression,
                                        Expression.Constant (source2)));
                }

                public static IQueryable<TSource> Union<TSource>(this IQueryable<TSource> source1, IEnumerable<TSource> source2, IEqualityComparer<TSource> comparer)
                {
                        Check.Source1AndSource2 (source1, source2);

                        return source1.Provider.CreateQuery<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source1.Expression,
                                        Expression.Constant (source2),
                                        Expression.Constant (comparer)));
                }


                #endregion

                #region Where

                public static IQueryable<TSource> Where<TSource> (this IQueryable<TSource> source, Expression<Func<TSource, bool>> predicate)
                {
                        Check.SourceAndPredicate (source, predicate);

                        return source.Provider.CreateQuery<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (predicate)));
                }

                public static IQueryable<TSource> Where<TSource> (this IQueryable<TSource> source, Expression<Func<TSource, int, bool>> predicate)
                {
                        Check.SourceAndPredicate (source, predicate);

                        return source.Provider.CreateQuery<TSource> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TSource)),
                                        source.Expression,
                                        Expression.Quote (predicate)));
                }


                #endregion

#if NET_4_0
                #region Zip

                public static IQueryable<TResult> Zip<TFirst, TSecond, TResult> (this IQueryable<TFirst> source1, IEnumerable<TSecond> source2, Expression<Func<TFirst, TSecond, TResult>> resultSelector)
                {
                        Check.Source1AndSource2 (source1, source2);
                        if (resultSelector == null)
                                throw new ArgumentNullException ("resultSelector");

                        return source1.Provider.CreateQuery<TResult> (
                                StaticCall (
                                        MakeGeneric (MethodBase.GetCurrentMethod (), typeof (TFirst), typeof (TSecond), typeof (TResult)),
                                        source1.Expression,
                                        Expression.Quote (resultSelector)));
                }

                #endregion
#endif
        }
}