memgraph/include/utils/iterator/map.hpp
Kruno Tomola Fabro df0bf6fa5f Database interface refactor.
DbAccessor:
 -Guarantees that access to Vertex and Edge is possible only through
 Vertex::Accessor and Edge::Accessor.
 -Guarantees that changing Vertex and Edge is possible only using
 Vertex::Accessor returned by vertex_insert() method and
 Edge::Accessor returned by edge_insert() method.
 -Offers CRUD for Vertex and Edge except iterating over all edges.

Squashed commit messages:

First step in database accessor refactoring done.
It's compiling.
All tests with exception of integration_querys pass

Tests now initialize logging facilities.

Refactored accessors.
RecordAccessor now has 3 states.
From,To,Out,In in there respecive Accessors return unfilled RecordAccessor.
Added iterator classes into utils/itearator/.
2016-08-15 00:09:58 +01:00

40 lines
725 B
C++

#pragma once
#include "utils/option.hpp"
namespace iter
{
template <class U, class I, class MapOperator>
class Map
{
public:
Map() = delete;
template <class IT, class OP>
Map(IT &&iter, OP &&op) : iter(std::move(iter)), op(std::move(op))
{
}
auto next()
{
auto item = iter.next();
if (item.is_present()) {
return Option<U>(op(item.take()));
} else {
return Option<U>();
}
}
private:
I iter;
MapOperator op;
};
template <class I, class OP>
auto make_map(I &&iter, OP &&op)
{
return Map<decltype(op(iter.next().take())), I, OP>(std::move(iter),
std::move(op));
}
}