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Diff-Listener: resolve template instantiation errors

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As it turned out, the reason was a missing move-ctor.
The base of the whole DSL-Stack, TreeMutator, is defined MoveOnly,
and this is also the intended use (build an anonymous instance
through the DSL and move it into the work buffer prior to diff application)

However, C++ does *cease to define* a move ctor implicitly,
whenever /one of the "big five" is defined explicitly/.

So Detector4StructuralChanges was the culprit, it defined a dtor,
but failed to define the move ctor explicitly.


So.... well, this did cost me several hours to track down,
yet I still rather do not want to write all those ctors explicitly all the time,
and so I am still in favour of implicitly generated ctors, even if they hurt sometimes.
This commit is contained in:
Fischlurch 2019-12-15 13:54:29 +01:00
parent 854f4eca58
commit 3e1d0036ed
4 changed files with 158 additions and 20 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

2
src/lib/diff/tree-mutator-collection-binding.hpp
View file

@ -164,7 +164,7 @@ namespace diff{
*/
template<class COLL, class MAT, class CTR, class SEL, class ASS, class MUT>
struct CollectionBinding
// : util::MoveOnly
: util::MoveOnly
{
using Coll = typename Strip<COLL>::TypeReferred;
using Elm = typename Coll::value_type;

9
src/lib/diff/tree-mutator-listener-binding.hpp
View file

@ -81,6 +81,9 @@ namespace diff{
, changeListener_{functor}
{ }
// move construction allowed and expected to happen
Detector4StructuralChanges (Detector4StructuralChanges&&) =default;
/** once the diff is for this level is completely applied,
* the TreeMutator will be discarded, and we can fire our
* change listener at that point. */
@ -105,16 +108,12 @@ namespace diff{
*/
template<class PAR>
template<typename LIS>
// inline Builder<Detector4StructuralChanges<PAR,LIS>>
inline auto
Builder<PAR>::onStructuralChange (LIS changeListener)
{
ASSERT_VALID_SIGNATURE (LIS, void(void))
using BIN = Detector4StructuralChanges<PAR,LIS>;
BIN furz{changeListener, move(*this)};
return Builder<BIN> (move (furz));
// return chainedBuilder<Detector4StructuralChanges<PAR,LIS>> (changeListener);
return chainedBuilder<Detector4StructuralChanges<PAR,LIS>> (changeListener);
}
}//(END)Mutator-Builder decorator components...

4
src/lib/diff/tree-mutator.hpp
View file

@ -141,7 +141,7 @@ namespace diff{
* activities to concrete manipulations known within target scope.
*/
class TreeMutator
// : util::MoveOnly
: util::MoveOnly
{
public:
@ -149,7 +149,7 @@ namespace diff{
// only default and move construction allowed
TreeMutator () =default;
// TreeMutator (TreeMutator&&) =default;
TreeMutator (TreeMutator&&) =default;

163
wiki/thinkPad.ichthyo.mm
View file

@ -36182,16 +36182,17 @@
</node>
</node>
</node>
<node BACKGROUND_COLOR="#fdfdcf" COLOR="#ff0000" CREATED="1576377684248" ID="ID_1419015987" MODIFIED="1576377692667" TEXT="Probleme mit der Builder-Konstruktion">
<icon BUILTIN="flag-pink"/>
<node COLOR="#338800" CREATED="1576377684248" ID="ID_1419015987" MODIFIED="1576414100918" TEXT="Probleme mit der Builder-Konstruktion">
<icon BUILTIN="button_ok"/>
<node CREATED="1576377697727" ID="ID_202863640" MODIFIED="1576377709748" TEXT="Template-Error....">
<icon BUILTIN="smiley-angry"/>
</node>
<node CREATED="1576377711045" ID="ID_108442931" MODIFIED="1576377734670" TEXT="seltsamerweise... denn im Prinzip das Gleiche funktioniert doch f&#xfc;r collection und Attribute"/>
<node CREATED="1576378164751" ID="ID_326483835" MODIFIED="1576378173210" TEXT="mehrere Probleme">
<node CREATED="1576378177126" ID="ID_940209297" MODIFIED="1576378184858" TEXT="doppelt gewickelter Builder tritt auf">
<node BACKGROUND_COLOR="#eee5c3" COLOR="#990000" CREATED="1576378190100" ID="ID_1161663563" MODIFIED="1576378200871" TEXT="Verdacht: implizite Konversion?">
<icon BUILTIN="flag-yellow"/>
<node COLOR="#435e98" CREATED="1576378177126" ID="ID_940209297" MODIFIED="1576413723637" TEXT="doppelt gewickelter Builder tritt auf">
<icon BUILTIN="messagebox_warning"/>
<node BACKGROUND_COLOR="#eee5c3" COLOR="#990000" CREATED="1576378190100" ID="ID_1161663563" MODIFIED="1576413711984" TEXT="Verdacht: implizite Konversion?">
<icon BUILTIN="broken-line"/>
</node>
<node CREATED="1576378201634" ID="ID_1282623104" MODIFIED="1576378225818" TEXT="mache mal den Builder-ctor explizit">
<node CREATED="1576378226991" ID="ID_553975580" MODIFIED="1576378241185" TEXT="den ein-elementigen Template ctor"/>
@ -36216,7 +36217,8 @@
</richcontent>
</node>
</node>
<node CREATED="1576378343418" ID="ID_1269344650" MODIFIED="1576378357653" TEXT="angeblich Aufruf gesperrter Copy-Ctorn">
<node COLOR="#435e98" CREATED="1576378343418" ID="ID_1269344650" MODIFIED="1576413734213" TEXT="angeblich Aufruf gesperrter Copy-Ctorn">
<icon BUILTIN="broken-line"/>
<node CREATED="1576378359957" ID="ID_1488794757" MODIFIED="1576378478485" TEXT="das ist immer ein Ketten-Argument">
<richcontent TYPE="NOTE"><html>
<head>
@ -36250,13 +36252,33 @@
</node>
<node CREATED="1576378580863" ID="ID_761583276" MODIFIED="1576378586645" TEXT="...dann gehts"/>
</node>
<node BACKGROUND_COLOR="#eee5c3" COLOR="#990000" CREATED="1576378589343" ID="ID_1164539927" MODIFIED="1576378607589" TEXT="also: irgendwo schwenkt die Kette auf einen copy-ctor um">
<icon BUILTIN="flag-yellow"/>
<node BACKGROUND_COLOR="#fdfdcf" COLOR="#ff0000" CREATED="1576378609851" ID="ID_669880694" MODIFIED="1576379532737" TEXT="Frage-1 : wo?">
<icon BUILTIN="flag-pink"/>
<node COLOR="#338800" CREATED="1576378589343" ID="ID_1164539927" MODIFIED="1576413693950" TEXT="also: irgendwo schwenkt die Kette auf einen copy-ctor um">
<icon BUILTIN="button_ok"/>
<node COLOR="#435e98" CREATED="1576378609851" ID="ID_669880694" MODIFIED="1576413678942" TEXT="Frage-1 : wo?">
<icon BUILTIN="help"/>
<node CREATED="1576413599727" ID="ID_601054330" MODIFIED="1576413602019" TEXT="in Detector4StructuralChanges"/>
<node CREATED="1576413602872" ID="ID_1037688378" MODIFIED="1576413616834" TEXT="der hat einen explizit definierten dtor"/>
<node CREATED="1576413622373" ID="ID_676470389" MODIFIED="1576413665197" TEXT="und damit keinen impliziten move-ctor mehr!!">
<richcontent TYPE="NOTE"><html>
<head>
</head>
<body>
<p>
selbst wenn er &#252;ber x Basisklassen von MoveOnly erbt
</p>
</body>
</html>
</richcontent>
<icon BUILTIN="clanbomber"/>
</node>
</node>
<node COLOR="#435e98" CREATED="1576378616851" ID="ID_1283591083" MODIFIED="1576413685202" TEXT="Frage-2 : warum?">
<icon BUILTIN="help"/>
<node CREATED="1576410342653" ID="ID_1010651919" MODIFIED="1576413594966" TEXT="weil der betr. move-Ctor nicht (implizit) definiert ist">
<arrowlink COLOR="#4963d8" DESTINATION="ID_1999847041" ENDARROW="Default" ENDINCLINATION="-4316;0;" ID="Arrow_ID_809724531" STARTARROW="None" STARTINCLINATION="-6312;349;"/>
<icon BUILTIN="info"/>
</node>
<node BACKGROUND_COLOR="#fdfdcf" COLOR="#ff0000" CREATED="1576378616851" ID="ID_1283591083" MODIFIED="1576379534177" TEXT="Frage-2 : warum?">
<icon BUILTIN="flag-pink"/>
</node>
</node>
</node>
@ -50932,6 +50954,123 @@
</node>
</node>
</node>
<node CREATED="1576410376184" ID="ID_1999847041" MODIFIED="1576413594967" TEXT="C++: Regeln f&#xfc;r implizite Ctor">
<linktarget COLOR="#4963d8" DESTINATION="ID_1999847041" ENDARROW="Default" ENDINCLINATION="-4316;0;" ID="Arrow_ID_809724531" SOURCE="ID_1010651919" STARTARROW="None" STARTINCLINATION="-6312;349;"/>
<node COLOR="#435e98" CREATED="1576411524771" ID="ID_1113045308" LINK="https://stackoverflow.com/a/13345578" MODIFIED="1576411545061" TEXT="Stackoverflow">
<icon BUILTIN="info"/>
</node>
<node CREATED="1576410536554" ID="ID_283720267" MODIFIED="1576410686060">
<richcontent TYPE="NODE"><html>
<head>
</head>
<body>
<p>
werden u.U sillschweigend <b>nicht</b>&#160;generiert
</p>
</body>
</html>
</richcontent>
<richcontent TYPE="NOTE"><html>
<head>
</head>
<body>
<p>
Wenn bestimmte Vorraussetzungen <i>nicht erf&#252;llt</i>&#160;sind, dann unterbleibt das automatische Injizieren eines generierten Konstruktors. Die Klasse verh&#228;lt sich dann so, als w&#228;re die btr. Definition nicht gegeben...
</p>
</body>
</html>
</richcontent>
<icon BUILTIN="messagebox_warning"/>
<node CREATED="1576410705370" ID="ID_1306160146" MODIFIED="1576410795799" TEXT="t&#xfc;ckisch: ggfs erwartetes implizites Verhalten findet nicht statt">
<richcontent TYPE="NOTE"><html>
<head>
</head>
<body>
<p>
d.h. Member-Init kann unterbleiben (bei elementaren Typen, wenn die Klasse damit ein POD wird).
</p>
<p>
Und noch h&#228;ufiger: wir schwenken von Move-Konstruktion auf Copy-Konstruktion um
</p>
</body>
</html>
</richcontent>
</node>
<node CREATED="1576410798222" ID="ID_589275948" MODIFIED="1576410813888" TEXT="Abhilfe: was wichtig ist, stets explizit definieren"/>
<node CREATED="1576412962086" ID="ID_714316723" MODIFIED="1576412969679" TEXT="Tip: Fehler provozieren">
<icon BUILTIN="idea"/>
<node CREATED="1576412971076" ID="ID_310988477" MODIFIED="1576412980494" TEXT="indem man explizit mal aufruft, was man erwartet"/>
<node CREATED="1576412981491" ID="ID_1451048709" MODIFIED="1576413215568" TEXT="Template-Traces lesen lernen....">
<richcontent TYPE="NOTE"><html>
<head>
</head>
<body>
<p>
error: use of deleted function Derived::Derived(const Derived &amp;)
</p>
<p>
note: Derived::Derived(const Derived &amp;)&#160;is implicitly deleted because the default definition would be ill-formed:
</p>
<p>
...und dann kommt der Fehler, der passieren <b>w&#252;rde</b>....
</p>
<p>
error: use of deleted function Base::Base(const Base&amp;)
</p>
<p>
note: Base::Base(const Base&amp;)&#160;&#160;is implicitly deleted because the default definition would be ill-formed:
</p>
<p>
error: use of deleted function SomeMember::SomeMember(const SomeMember &amp;)
</p>
<p>
</p>
<p>
...
</p>
<p>
...
</p>
<p>
...
</p>
<p>
...
</p>
<p>
...
</p>
</body>
</html>
</richcontent>
<icon BUILTIN="ksmiletris"/>
<node CREATED="1576413219987" ID="ID_601627408" MODIFIED="1576413226208" TEXT="der Compiler ist Dein Froind"/>
</node>
</node>
</node>
<node CREATED="1576411548659" ID="ID_1088124413" MODIFIED="1576411553075" TEXT="default-ctor">
<node CREATED="1576411555738" ID="ID_810441855" MODIFIED="1576411577563" TEXT="nicht wenn irgend ein Member inline initialisiert wird!"/>
</node>
<node CREATED="1576411594053" ID="ID_181876076" MODIFIED="1576411598691" TEXT="copy/move">
<node CREATED="1576411599805" ID="ID_492402771" MODIFIED="1576411615709" TEXT="nicht wenn auch nur einer der &quot;big five&quot; definiert ist"/>
<node CREATED="1576411616722" ID="ID_38658612" MODIFIED="1576411634218" TEXT="Achtung: im Besonderen der dtor schaltet damit Auto-Generierun ab"/>
</node>
<node CREATED="1576411685336" ID="ID_168955305" MODIFIED="1576411687363" TEXT="move">
<node CREATED="1576411688040" ID="ID_430174340" MODIFIED="1576411707490" TEXT="wenn der generierte move-Code irgendwo einen Fehler produzieren w&#xfc;rde"/>
<node CREATED="1576411708150" ID="ID_728246628" MODIFIED="1576411719224" TEXT="das kann mehrere Ebenen tief rekursiv der Fall sein"/>
<node CREATED="1576411733367" ID="ID_1365339586" MODIFIED="1576411734752" TEXT="Tips">
<node CREATED="1576411735874" ID="ID_240070307" MODIFIED="1576411738544" TEXT="Referenzen"/>
<node CREATED="1576411739241" ID="ID_1459661901" MODIFIED="1576411778582" TEXT="Member/Basisklassen bei denen ebenfalls die implizite Generierung unterbleibt"/>
<node CREATED="1576411779540" ID="ID_816697044" MODIFIED="1576411801603" TEXT="ein nicht verf&#xfc;gbarer/aufrufbarer dtor (wegen move!)"/>
<node CREATED="1576411803728" ID="ID_1798497956" MODIFIED="1576411812841" TEXT="Variant-Typen (unions)"/>
</node>
</node>
</node>
</node>
</node>
<node CREATED="1450488895106" ID="ID_1586185818" MODIFIED="1557498707240" TEXT="Threading">