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//
// QueryableEnumerable<TElement>.cs
//
// Authors:
// Roei Erez (roeie@mainsoft.com)
// Jb Evain (jbevain@novell.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;
using System.Linq.Expressions;
namespace System.Linq {
interface IQueryableEnumerable : IQueryable {
IEnumerable GetEnumerable ();
}
interface IQueryableEnumerable<TElement> : IQueryableEnumerable, IQueryable<TElement>, IOrderedQueryable<TElement> {
}
class QueryableEnumerable<TElement> : IQueryableEnumerable<TElement>, IQueryProvider {
Expression expression;
IEnumerable<TElement> enumerable;
public Type ElementType {
get { return typeof (TElement); }
}
public Expression Expression {
get { return expression; }
}
public IQueryProvider Provider {
get { return this; }
}
public QueryableEnumerable (IEnumerable<TElement> enumerable)
{
this.expression = Expression.Constant (this);
this.enumerable = enumerable;
}
public QueryableEnumerable (Expression expression)
{
this.expression = expression;
}
public IEnumerable GetEnumerable ()
{
return enumerable;
}
IEnumerator IEnumerable.GetEnumerator ()
{
return GetEnumerator ();
}
public IEnumerator<TElement> GetEnumerator ()
{
return Execute<IEnumerable<TElement>> (expression).GetEnumerator ();
}
public IQueryable CreateQuery (Expression expression)
{
return (IQueryable) Activator.CreateInstance (
typeof (QueryableEnumerable<>).MakeGenericType (
expression.Type.GetFirstGenericArgument ()), expression);
}
public object Execute (Expression expression)
{
var lambda = Expression.Lambda (TransformQueryable (expression));
return lambda.Compile ().DynamicInvoke ();
}
static Expression TransformQueryable (Expression expression)
{
#if NET_4_0 || BOOTSTRAP_NET_4_0
throw new NotImplementedException ();
#else
return new QueryableTransformer ().Transform (expression);
#endif
}
public IQueryable<TElem> CreateQuery<TElem> (Expression expression)
{
return new QueryableEnumerable<TElem> (expression);
}
public TResult Execute<TResult> (Expression expression)
{
var lambda = Expression.Lambda<Func<TResult>> (TransformQueryable (expression));
return lambda.Compile ().Invoke ();
}
public override string ToString ()
{
if (enumerable != null)
return enumerable.ToString ();
if (expression == null)
return base.ToString ();
var constant = expression as ConstantExpression;
if (constant != null && constant.Value == this)
return base.ToString ();
return expression.ToString ();
}
}
}
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