move and split drafted code to the acutal library headers
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5 changed files with 587 additions and 210 deletions
282
src/lib/diff/index-table.hpp
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282
src/lib/diff/index-table.hpp
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/*
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INDEX-TABLE.hpp - helper for lookup and membership check of sequence like data
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Copyright (C) Lumiera.org
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2015, Hermann Vosseler <Ichthyostega@web.de>
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This program is free software; you can redistribute it and/or
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modify it under the terms of the GNU General Public License as
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published by the Free Software Foundation; either version 2 of
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the License, or (at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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*/
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/** @file index-table.hpp
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** Generic lookup table for a sequence of unique values.
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** This helper facility for detecting differences in data sequences
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** takes a snapshot of the data at construction time and builds a lookup tree.
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** This allows to find the index position of a given key element, and to detect
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** membership.
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**
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** @see diff-index-table-test.cpp
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** @see diff-list-generation-test.cpp
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** @see DiffDetector
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**
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*/
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#ifndef LIB_DIFF_INDEX_TABLE_H
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#define LIB_DIFF_INDEX_TABLE_H
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#include "lib/diff/list-diff.hpp"
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#include "lib/format-string.hpp"
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#include <algorithm>
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#include <vector>
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#include <tuple>
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namespace lib {
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namespace diff{
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#include "lib/test/run.hpp"
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#include "lib/diff/list-diff.hpp"
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#include "lib/iter-adapter.hpp"
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#include "lib/itertools.hpp"
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#include "lib/util.hpp"
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#include <boost/noncopyable.hpp>
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#include <string>
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#include <vector>
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using lib::append_all;
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using util::unConst;
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using util::isnil;
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using std::string;
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using std::vector;
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using std::move;
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using std::swap;
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namespace lib {
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namespace diff{
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//#########################
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template<typename VAL>
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class IndexTable
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{
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public:
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template<class SEQ>
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IndexTable(SEQ const& seq)
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{
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UNIMPLEMENTED("build index");
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}
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size_t
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size() const
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{
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UNIMPLEMENTED("sequence size");
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}
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VAL const&
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getElement (size_t i) const
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{
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UNIMPLEMENTED("indexed value access");
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}
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bool
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contains (VAL const& elm) const
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{
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return size() == pos(elm);
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}
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size_t
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pos (VAL const& elm) const
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{
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UNIMPLEMENTED("index lookup");
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}
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};
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template<class SEQ>
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class DiffDetector
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: boost::noncopyable
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{
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using Val = typename SEQ::value_type;
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using Idx = IndexTable<Val>;
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Idx refIdx_;
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SEQ const& currentData_;
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using DiffStep = typename ListDiffLanguage<Val>::DiffStep;
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/** @internal state frame for diff detection and generation. */
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class DiffFrame;
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public:
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explicit
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DiffDetector(SEQ const& refSeq)
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: refIdx_(refSeq)
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, currentData_(refSeq)
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{ }
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/** does the current state of the underlying sequence differ
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* from the state embodied into the last reference snapshot taken?
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* @remarks will possibly evaluate and iterate the whole sequence
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*/
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bool
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isChanged() const
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{
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UNIMPLEMENTED("change detection");
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}
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/** Diff is a iterator to yield a sequence of DiffStep elements */
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using Diff = lib::IterStateWrapper<DiffStep, DiffFrame>;
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/** Diff generation core operation.
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* Take a snapshot of the \em current state of the underlying sequence
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* and establish a frame to find the differences to the previously captured
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* \em old state. This possible difference evaluation is embodied into a #Diff
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* iterator and handed over to the client, while the snapshot of the current state
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* becomes the new reference point from now on.
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* @return iterator to yield a sequence of DiffStep tokens, which describe the changes
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* between the previous reference state and the current state of the sequence.
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* @note takes a new snapshot to supersede the old one, i.e. updates the DiffDetector.
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* @warning the returned iterator retains a reference to the current (new) snapshot.
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* Any concurrent modification leads to undefined behaviour. You must not
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* invoke #pullUpdate while another client still explores the result
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* of an old evaluation.
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*/
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Diff
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pullUpdate()
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{
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Idx mark (currentData_);
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swap (mark, refIdx_); // mark now refers to old reference point
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return Diff(DiffFrame(refIdx_, move(mark)));
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}
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};
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/**
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* A diff generation process is built on top of an "old" reference point
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* and a "new" state of the underlying sequence. Within this reference frame,
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* an demand-driven evaluation of the differences is handed out to the client
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* as an iterator. While consuming this evaluation process, both the old and
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* the new version of the sequence will be traversed once. In case of re-orderings,
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* a nested forward lookup similar to insertion sort will look for matches in the
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* old sequence, rendering the whole evaluation quadratic in worst-case.
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*/
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template<class SEQ>
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class DiffDetector<SEQ>::DiffFrame
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{
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Idx old_;
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Idx* new_;
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size_t oldHead_=0,
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newHead_=0;
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static ListDiffLanguage<Val> token;
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DiffStep currentStep_;
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public:
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DiffFrame(Idx& current, Idx&& refPoint)
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: old_(refPoint)
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, new_(¤t)
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, currentStep_(establishNextState())
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{ }
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/* === Iteration control API for IterStateWrapper== */
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friend bool
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checkPoint (DiffFrame const& frame)
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{
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return token.NIL != frame.currentStep_;
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}
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friend DiffStep&
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yield (DiffFrame const& frame)
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{
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REQUIRE (checkPoint (frame));
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return unConst(frame).currentStep_;
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}
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friend void
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iterNext (DiffFrame & frame)
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{
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frame.establishNextState();
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}
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private:
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DiffStep
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establishNextState()
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{
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if (canPick())
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{
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consumeOld();
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return token.pick (consumeNew());
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}
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if (canDelete())
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return token.del (consumeOld());
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if (canInsert())
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return token.ins (consumeNew());
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if (needFetch())
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return token.find (consumeNew());
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if (obsoleted())
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return token.skip (consumeOld());
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return token.NIL;
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}
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bool hasOld() const { return oldHead_ < old_.size(); }
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bool hasNew() const { return newHead_ < new_->size(); }
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bool canPick() const { return hasOld() && hasNew() && oldElm()==newElm(); }
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bool canDelete() const { return hasOld() && !new_->contains(oldElm()); }
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bool canInsert() const { return hasNew() && !old_.contains(newElm()); }
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bool needFetch() const { return hasNew() && oldHead_ < old_.pos(newElm()); }
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bool obsoleted() const { return hasOld() && newHead_ > new_->pos(oldElm()); }
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Val const& oldElm() const { return old_.getElement (oldHead_); }
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Val const& newElm() const { return new_->getElement (newHead_); }
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Val const& consumeOld() { return old_.getElement (oldHead_++); }
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Val const& consumeNew() { return new_->getElement (newHead_++); }
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};
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/** allocate static storage for the diff language token builder functions */
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template<class SEQ>
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ListDiffLanguage<typename DiffDetector<SEQ>::Val> DiffDetector<SEQ>::DiffFrame::token;
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//#########################
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}} // namespace lib::diff
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#endif /*LIB_DIFF_INDEX_TABLE_H*/
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@ -1,5 +1,5 @@
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/*
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LIST-DIFF-APPLICATION.hpp - language to describe differences in linearised form
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LIST-DIFF-APPLICATION.hpp - consume and apply a list diff
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Copyright (C) Lumiera.org
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2014, Hermann Vosseler <Ichthyostega@web.de>
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|
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302
src/lib/diff/list-diff-detector.hpp
Normal file
302
src/lib/diff/list-diff-detector.hpp
Normal file
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@ -0,0 +1,302 @@
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/*
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LIST-DIFF-DETECTOR.hpp - language to describe differences in linearised form
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Copyright (C) Lumiera.org
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2015, Hermann Vosseler <Ichthyostega@web.de>
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|
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This program is free software; you can redistribute it and/or
|
||||
modify it under the terms of the GNU General Public License as
|
||||
published by the Free Software Foundation; either version 2 of
|
||||
the License, or (at your option) any later version.
|
||||
|
||||
This program is distributed in the hope that it will be useful,
|
||||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||||
GNU General Public License for more details.
|
||||
|
||||
You should have received a copy of the GNU General Public License
|
||||
along with this program; if not, write to the Free Software
|
||||
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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*/
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/** @file list-diff-detector.hpp
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** Compare two data sequences to find or describe differences.
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** The DiffDetector defined here takes snapshot(s) from a monitored generic
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** data structure and generates a description of differences in a linearised
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** list diff language. Once initiated, the investigation of the old and new
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** sequence snapshot, combined with generation of a sequence of diff description
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** verbs, proceeds demand driven. The client "takes" a DiffFrame, which acts
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** as iterator to extract the diff progressively; when initiating such a
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** diff generation process, a new baseline snapshot from the underlying
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** data is taken to replace the old baseline.
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**
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** \par List Diff Algorithm
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** A fundamental decision taken here is to process the differences in a stream
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** processing fashion. This renders the usage of data index numbers undesirable.
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** Moreover, we do not want to assume anything about the consumer; the diff might
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** be transformed into a textual representation, or it may be applied to quite
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** another target data structure.
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**
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** The implementation is built using a simplistic method and is certainly far from
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** optimal. For one, we're taking snapshots, and we're building an index table
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** for each snapshot, in order to distinguish inserted and deleted elements from
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** mismatches due to sequence re-ordering. And for the description of permutations,
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** we use a processing pattern similar to insertion sort. This allows for a very
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** simple generation mechanism, but requires the receiver of the diff to scan
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** down into the remainder of the data to find and fetch elements out-of-order.
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**
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** @see diff-list-generation-test.cpp
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** @see DiffApplicationStrategy
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** @see ListDiffLanguage
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**
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*/
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#ifndef LIB_DIFF_LIST_DIFF_DETECTOR_H
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#define LIB_DIFF_LIST_DIFF_DETECTOR_H
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#include "lib/diff/list-diff.hpp"
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#include "lib/format-string.hpp"
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#include <algorithm>
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#include <vector>
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#include <tuple>
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|
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|
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namespace lib {
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namespace diff{
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#include "lib/test/run.hpp"
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#include "lib/diff/list-diff.hpp"
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#include "lib/iter-adapter.hpp"
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#include "lib/itertools.hpp"
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#include "lib/util.hpp"
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|
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#include <boost/noncopyable.hpp>
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#include <string>
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#include <vector>
|
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|
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using lib::append_all;
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using util::unConst;
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using util::isnil;
|
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using std::string;
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using std::vector;
|
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using std::move;
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using std::swap;
|
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|
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|
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namespace lib {
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namespace diff{
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//#########################
|
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|
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template<typename VAL>
|
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class IndexTable
|
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{
|
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public:
|
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template<class SEQ>
|
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IndexTable(SEQ const& seq)
|
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{
|
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UNIMPLEMENTED("build index");
|
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}
|
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|
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size_t
|
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size() const
|
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{
|
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UNIMPLEMENTED("sequence size");
|
||||
}
|
||||
|
||||
VAL const&
|
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getElement (size_t i) const
|
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{
|
||||
UNIMPLEMENTED("indexed value access");
|
||||
}
|
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|
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bool
|
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contains (VAL const& elm) const
|
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{
|
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return size() == pos(elm);
|
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}
|
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|
||||
size_t
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pos (VAL const& elm) const
|
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{
|
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UNIMPLEMENTED("index lookup");
|
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}
|
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};
|
||||
|
||||
|
||||
|
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|
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|
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|
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template<class SEQ>
|
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class DiffDetector
|
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: boost::noncopyable
|
||||
{
|
||||
using Val = typename SEQ::value_type;
|
||||
using Idx = IndexTable<Val>;
|
||||
|
||||
Idx refIdx_;
|
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SEQ const& currentData_;
|
||||
|
||||
|
||||
using DiffStep = typename ListDiffLanguage<Val>::DiffStep;
|
||||
|
||||
/** @internal state frame for diff detection and generation. */
|
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class DiffFrame;
|
||||
|
||||
|
||||
|
||||
|
||||
public:
|
||||
explicit
|
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DiffDetector(SEQ const& refSeq)
|
||||
: refIdx_(refSeq)
|
||||
, currentData_(refSeq)
|
||||
{ }
|
||||
|
||||
|
||||
/** does the current state of the underlying sequence differ
|
||||
* from the state embodied into the last reference snapshot taken?
|
||||
* @remarks will possibly evaluate and iterate the whole sequence
|
||||
*/
|
||||
bool
|
||||
isChanged() const
|
||||
{
|
||||
UNIMPLEMENTED("change detection");
|
||||
}
|
||||
|
||||
|
||||
/** Diff is a iterator to yield a sequence of DiffStep elements */
|
||||
using Diff = lib::IterStateWrapper<DiffStep, DiffFrame>;
|
||||
|
||||
/** Diff generation core operation.
|
||||
* Take a snapshot of the \em current state of the underlying sequence
|
||||
* and establish a frame to find the differences to the previously captured
|
||||
* \em old state. This possible difference evaluation is embodied into a #Diff
|
||||
* iterator and handed over to the client, while the snapshot of the current state
|
||||
* becomes the new reference point from now on.
|
||||
* @return iterator to yield a sequence of DiffStep tokens, which describe the changes
|
||||
* between the previous reference state and the current state of the sequence.
|
||||
* @note takes a new snapshot to supersede the old one, i.e. updates the DiffDetector.
|
||||
* @warning the returned iterator retains a reference to the current (new) snapshot.
|
||||
* Any concurrent modification leads to undefined behaviour. You must not
|
||||
* invoke #pullUpdate while another client still explores the result
|
||||
* of an old evaluation.
|
||||
*/
|
||||
Diff
|
||||
pullUpdate()
|
||||
{
|
||||
Idx mark (currentData_);
|
||||
swap (mark, refIdx_); // mark now refers to old reference point
|
||||
return Diff(DiffFrame(refIdx_, move(mark)));
|
||||
}
|
||||
};
|
||||
|
||||
|
||||
|
||||
|
||||
/**
|
||||
* A diff generation process is built on top of an "old" reference point
|
||||
* and a "new" state of the underlying sequence. Within this reference frame,
|
||||
* an demand-driven evaluation of the differences is handed out to the client
|
||||
* as an iterator. While consuming this evaluation process, both the old and
|
||||
* the new version of the sequence will be traversed once. In case of re-orderings,
|
||||
* a nested forward lookup similar to insertion sort will look for matches in the
|
||||
* old sequence, rendering the whole evaluation quadratic in worst-case.
|
||||
*/
|
||||
template<class SEQ>
|
||||
class DiffDetector<SEQ>::DiffFrame
|
||||
{
|
||||
Idx old_;
|
||||
Idx* new_;
|
||||
size_t oldHead_=0,
|
||||
newHead_=0;
|
||||
|
||||
static ListDiffLanguage<Val> token;
|
||||
|
||||
DiffStep currentStep_;
|
||||
|
||||
|
||||
public:
|
||||
DiffFrame(Idx& current, Idx&& refPoint)
|
||||
: old_(refPoint)
|
||||
, new_(¤t)
|
||||
, currentStep_(establishNextState())
|
||||
{ }
|
||||
|
||||
|
||||
/* === Iteration control API for IterStateWrapper== */
|
||||
|
||||
friend bool
|
||||
checkPoint (DiffFrame const& frame)
|
||||
{
|
||||
return token.NIL != frame.currentStep_;
|
||||
}
|
||||
|
||||
friend DiffStep&
|
||||
yield (DiffFrame const& frame)
|
||||
{
|
||||
REQUIRE (checkPoint (frame));
|
||||
return unConst(frame).currentStep_;
|
||||
}
|
||||
|
||||
friend void
|
||||
iterNext (DiffFrame & frame)
|
||||
{
|
||||
frame.establishNextState();
|
||||
}
|
||||
|
||||
private:
|
||||
DiffStep
|
||||
establishNextState()
|
||||
{
|
||||
if (canPick())
|
||||
{
|
||||
consumeOld();
|
||||
return token.pick (consumeNew());
|
||||
}
|
||||
if (canDelete())
|
||||
return token.del (consumeOld());
|
||||
if (canInsert())
|
||||
return token.ins (consumeNew());
|
||||
if (needFetch())
|
||||
return token.find (consumeNew());
|
||||
if (obsoleted())
|
||||
return token.skip (consumeOld());
|
||||
|
||||
return token.NIL;
|
||||
}
|
||||
|
||||
bool hasOld() const { return oldHead_ < old_.size(); }
|
||||
bool hasNew() const { return newHead_ < new_->size(); }
|
||||
bool canPick() const { return hasOld() && hasNew() && oldElm()==newElm(); }
|
||||
bool canDelete() const { return hasOld() && !new_->contains(oldElm()); }
|
||||
bool canInsert() const { return hasNew() && !old_.contains(newElm()); }
|
||||
bool needFetch() const { return hasNew() && oldHead_ < old_.pos(newElm()); }
|
||||
bool obsoleted() const { return hasOld() && newHead_ > new_->pos(oldElm()); }
|
||||
|
||||
Val const& oldElm() const { return old_.getElement (oldHead_); }
|
||||
Val const& newElm() const { return new_->getElement (newHead_); }
|
||||
Val const& consumeOld() { return old_.getElement (oldHead_++); }
|
||||
Val const& consumeNew() { return new_->getElement (newHead_++); }
|
||||
};
|
||||
|
||||
|
||||
/** allocate static storage for the diff language token builder functions */
|
||||
template<class SEQ>
|
||||
ListDiffLanguage<typename DiffDetector<SEQ>::Val> DiffDetector<SEQ>::DiffFrame::token;
|
||||
|
||||
|
||||
//#########################
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
}} // namespace lib::diff
|
||||
#endif /*LIB_DIFF_LIST_DIFF_DETECTOR_H*/
|
||||
|
|
@ -1,5 +1,5 @@
|
|||
/*
|
||||
LIST-DIFF.hpp - language to describe differences in linearised form
|
||||
LIST-DIFF.hpp - language to describe differences between list like sequences
|
||||
|
||||
Copyright (C) Lumiera.org
|
||||
2014, Hermann Vosseler <Ichthyostega@web.de>
|
||||
|
|
|
|||
|
|
@ -22,228 +22,21 @@
|
|||
|
||||
|
||||
#include "lib/test/run.hpp"
|
||||
#include "lib/diff/list-diff.hpp"
|
||||
#include "lib/iter-adapter.hpp"
|
||||
#include "lib/diff/list-diff-detector.hpp"
|
||||
#include "lib/itertools.hpp"
|
||||
#include "lib/util.hpp"
|
||||
|
||||
#include <boost/noncopyable.hpp>
|
||||
#include <string>
|
||||
#include <vector>
|
||||
|
||||
using lib::append_all;
|
||||
using util::unConst;
|
||||
using util::isnil;
|
||||
using std::string;
|
||||
using std::vector;
|
||||
using std::move;
|
||||
using std::swap;
|
||||
|
||||
|
||||
namespace lib {
|
||||
namespace diff{
|
||||
//#########################
|
||||
|
||||
template<typename VAL>
|
||||
class IndexTable
|
||||
{
|
||||
public:
|
||||
template<class SEQ>
|
||||
IndexTable(SEQ const& seq)
|
||||
{
|
||||
UNIMPLEMENTED("build index");
|
||||
}
|
||||
|
||||
size_t
|
||||
size() const
|
||||
{
|
||||
UNIMPLEMENTED("sequence size");
|
||||
}
|
||||
|
||||
VAL const&
|
||||
getElement (size_t i) const
|
||||
{
|
||||
UNIMPLEMENTED("indexed value access");
|
||||
}
|
||||
|
||||
bool
|
||||
contains (VAL const& elm) const
|
||||
{
|
||||
return size() == pos(elm);
|
||||
}
|
||||
|
||||
size_t
|
||||
pos (VAL const& elm) const
|
||||
{
|
||||
UNIMPLEMENTED("index lookup");
|
||||
}
|
||||
};
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
template<class SEQ>
|
||||
class DiffDetector
|
||||
: boost::noncopyable
|
||||
{
|
||||
using Val = typename SEQ::value_type;
|
||||
using Idx = IndexTable<Val>;
|
||||
|
||||
Idx refIdx_;
|
||||
SEQ const& currentData_;
|
||||
|
||||
|
||||
using DiffStep = typename ListDiffLanguage<Val>::DiffStep;
|
||||
|
||||
/** @internal state frame for diff detection and generation. */
|
||||
class DiffFrame;
|
||||
|
||||
|
||||
|
||||
|
||||
public:
|
||||
explicit
|
||||
DiffDetector(SEQ const& refSeq)
|
||||
: refIdx_(refSeq)
|
||||
, currentData_(refSeq)
|
||||
{ }
|
||||
|
||||
|
||||
/** does the current state of the underlying sequence differ
|
||||
* from the state embodied into the last reference snapshot taken?
|
||||
* @remarks will possibly evaluate and iterate the whole sequence
|
||||
*/
|
||||
bool
|
||||
isChanged() const
|
||||
{
|
||||
UNIMPLEMENTED("change detection");
|
||||
}
|
||||
|
||||
|
||||
/** Diff is a iterator to yield a sequence of DiffStep elements */
|
||||
using Diff = lib::IterStateWrapper<DiffStep, DiffFrame>;
|
||||
|
||||
/** Diff generation core operation.
|
||||
* Take a snapshot of the \em current state of the underlying sequence
|
||||
* and establish a frame to find the differences to the previously captured
|
||||
* \em old state. This possible difference evaluation is embodied into a #Diff
|
||||
* iterator and handed over to the client, while the snapshot of the current state
|
||||
* becomes the new reference point from now on.
|
||||
* @return iterator to yield a sequence of DiffStep tokens, which describe the changes
|
||||
* between the previous reference state and the current state of the sequence.
|
||||
* @note takes a new snapshot to supersede the old one, i.e. updates the DiffDetector.
|
||||
* @warning the returned iterator retains a reference to the current (new) snapshot.
|
||||
* Any concurrent modification leads to undefined behaviour. You must not
|
||||
* invoke #pullUpdate while another client still explores the result
|
||||
* of an old evaluation.
|
||||
*/
|
||||
Diff
|
||||
pullUpdate()
|
||||
{
|
||||
Idx mark (currentData_);
|
||||
swap (mark, refIdx_); // mark now refers to old reference point
|
||||
return Diff(DiffFrame(refIdx_, move(mark)));
|
||||
}
|
||||
};
|
||||
|
||||
|
||||
|
||||
|
||||
/**
|
||||
* A diff generation process is built on top of an "old" reference point
|
||||
* and a "new" state of the underlying sequence. Within this reference frame,
|
||||
* an demand-driven evaluation of the differences is handed out to the client
|
||||
* as an iterator. While consuming this evaluation process, both the old and
|
||||
* the new version of the sequence will be traversed once. In case of re-orderings,
|
||||
* a nested forward lookup similar to insertion sort will look for matches in the
|
||||
* old sequence, rendering the whole evaluation quadratic in worst-case.
|
||||
*/
|
||||
template<class SEQ>
|
||||
class DiffDetector<SEQ>::DiffFrame
|
||||
{
|
||||
Idx old_;
|
||||
Idx* new_;
|
||||
size_t oldHead_=0,
|
||||
newHead_=0;
|
||||
|
||||
static ListDiffLanguage<Val> token;
|
||||
|
||||
DiffStep currentStep_;
|
||||
|
||||
|
||||
public:
|
||||
DiffFrame(Idx& current, Idx&& refPoint)
|
||||
: old_(refPoint)
|
||||
, new_(¤t)
|
||||
, currentStep_(establishNextState())
|
||||
{ }
|
||||
|
||||
|
||||
/* === Iteration control API for IterStateWrapper== */
|
||||
|
||||
friend bool
|
||||
checkPoint (DiffFrame const& frame)
|
||||
{
|
||||
return token.NIL != frame.currentStep_;
|
||||
}
|
||||
|
||||
friend DiffStep&
|
||||
yield (DiffFrame const& frame)
|
||||
{
|
||||
REQUIRE (checkPoint (frame));
|
||||
return unConst(frame).currentStep_;
|
||||
}
|
||||
|
||||
friend void
|
||||
iterNext (DiffFrame & frame)
|
||||
{
|
||||
frame.establishNextState();
|
||||
}
|
||||
|
||||
private:
|
||||
DiffStep
|
||||
establishNextState()
|
||||
{
|
||||
if (canPick())
|
||||
{
|
||||
consumeOld();
|
||||
return token.pick (consumeNew());
|
||||
}
|
||||
if (canDelete())
|
||||
return token.del (consumeOld());
|
||||
if (canInsert())
|
||||
return token.ins (consumeNew());
|
||||
if (needFetch())
|
||||
return token.find (consumeNew());
|
||||
if (obsoleted())
|
||||
return token.skip (consumeOld());
|
||||
|
||||
return token.NIL;
|
||||
}
|
||||
|
||||
bool hasOld() const { return oldHead_ < old_.size(); }
|
||||
bool hasNew() const { return newHead_ < new_->size(); }
|
||||
bool canPick() const { return hasOld() && hasNew() && oldElm()==newElm(); }
|
||||
bool canDelete() const { return hasOld() && !new_->contains(oldElm()); }
|
||||
bool canInsert() const { return hasNew() && !old_.contains(newElm()); }
|
||||
bool needFetch() const { return hasNew() && oldHead_ < old_.pos(newElm()); }
|
||||
bool obsoleted() const { return hasOld() && newHead_ > new_->pos(oldElm()); }
|
||||
|
||||
Val const& oldElm() const { return old_.getElement (oldHead_); }
|
||||
Val const& newElm() const { return new_->getElement (newHead_); }
|
||||
Val const& consumeOld() { return old_.getElement (oldHead_++); }
|
||||
Val const& consumeNew() { return new_->getElement (newHead_++); }
|
||||
};
|
||||
|
||||
|
||||
/** allocate static storage for the diff language token builder functions */
|
||||
template<class SEQ>
|
||||
ListDiffLanguage<typename DiffDetector<SEQ>::Val> DiffDetector<SEQ>::DiffFrame::token;
|
||||
|
||||
|
||||
//#########################
|
||||
namespace test{
|
||||
|
||||
namespace {//Test fixture....
|
||||
|
|
|
|||
Loading…
Reference in a new issue