Extract `include` func to dsymbolsem

[dchidindu5]

public bool addisdone = false; /// true if members have been added to scope
public bool onStack = false;

This variables were private before I had to change it to public because I encountered errors like undefined identifier onStack and addisdone`

Still working on them though

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[dchidindu5]

can it be casted? e.gLine 7539- cast(void) cache;

what about return null ? e.g line 7535 Can it be removed entirely or to be casted? @thewilsonator

[dchidindu5]

What's the appropriate way to cast this return condition.include(cdc._scope ? cdc._scope : sc) ? decl : cdc.elsedecl;

[thewilsonator]

Looking good! You will need to update dmd/compiler/src/tests/cxxfrontend.cc:

home/runner/work/dmd/dmd/dmd/compiler/src/tests/cxxfrontend.cc: In member function ‘virtual void MiniGlueVisitor::visit(TypeStruct*)’:
/home/runner/work/dmd/dmd/dmd/compiler/src/tests/cxxfrontend.cc:795:35: error: ‘class AttribDeclaration’ has no member named ‘include’
  795 |                     (void)attrib->include(NULL);
      |                                   ^~~~~~~
/home/runner/work/dmd/dmd/dmd/compiler/src/tests/cxxfrontend.cc: In member function ‘virtual void MiniGlueVisitor::visit(TypeClass*)’:
/home/runner/work/dmd/dmd/dmd/compiler/src/tests/cxxfrontend.cc:857:35: error: ‘class AttribDeclaration’ has no member named ‘include’
  857 |                     (void)attrib->include(NULL);
      |                                   ^~~~~~~
/home/runner/work/dmd/dmd/dmd/compiler/src/tests/cxxfrontend.cc: In member function ‘virtual void MiniGlueVisitor::visit(AttribDeclaration*)’:
/home/runner/work/dmd/dmd/dmd/compiler/src/tests/cxxfrontend.cc:1237:27: error: ‘class AttribDeclaration’ has no member named ‘include’
 1237 |         Dsymbols *ds = d->include(NULL);

[dchidindu5]

Thank you all, over to the next