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// Copyright (c) Microsoft Open Technologies, Inc. All rights reserved. See License.txt in the project root for license information.
#if !defined(CPPLINQ_LINQ_SELECT_HPP)
#define CPPLINQ_LINQ_SELECT_HPP
#pragma once
namespace cpplinq
{
template <class Collection, class Selector>
class linq_select
{
typedef typename Collection::cursor
inner_cursor;
public:
struct cursor {
typedef typename util::result_of<Selector(typename inner_cursor::element_type)>::type
reference_type;
typedef typename std::remove_reference<reference_type>::type
element_type;
typedef typename inner_cursor::cursor_category
cursor_category;
cursor(const inner_cursor& cur, Selector sel) : cur(cur), sel(std::move(sel)) {}
void forget() { cur.forget(); }
bool empty() const { return cur.empty(); }
void inc() { cur.inc(); }
reference_type get() const { return sel(cur.get()); }
bool atbegin() const { return cur.atbegin(); }
void dec() { cur.dec(); }
void skip(size_t n) { cur.skip(n); }
size_t position() const { return cur.position(); }
size_t size() const { return cur.size(); }
private:
inner_cursor cur;
Selector sel;
};
linq_select(const Collection& c, Selector sel) : c(c), sel(sel) {}
cursor get_cursor() const { return cursor(c.get_cursor(), sel); }
private:
Collection c;
Selector sel;
};
}
#endif // defined(CPPLINQ_LINQ_SELECT_HPP)
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