library/cpp/yson_pull/range.h


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#pragma once 
 
#include "reader.h" 
 
#include <util/generic/iterator.h> 
 
namespace NYsonPull { 
    class TStreamEventsRange: public TInputRangeAdaptor<TStreamEventsRange> {
        TReader Reader_;
        bool AtEnd;
 
    public:
        TStreamEventsRange(THolder<NInput::IStream> stream, EStreamType mode) 
            : Reader_{std::move(stream), mode}
            , AtEnd(false)
        {
        }
 
        const TEvent* Last() const noexcept {
            return &Reader_.LastEvent(); 
        }
 
        const TEvent* Next() {
            if (Y_UNLIKELY(AtEnd)) {
                return nullptr;
            }
 
            auto* event = &Reader_.NextEvent(); 
            if (event->Type() == EEventType::EndStream) { 
                AtEnd = true;
            }
            return event;
        } 
    };
}