ListSort.mesaTheListSortinterfacecontainsasingleprocedure,Sort,thatefficientlysortsaLISTofaspecifictype.Thepackage'simplementationusesthe"onlinemergesort"algorithmtosortann-itemlistintimeO(nlogn).ListSortsortslistsofItem,whereItem(andaprocedureforcomparingtwoItems)isdefinedinadefinitionsmodulethatparameterizestheinterface.AuserofthispackagecreatesasuitabledefinitionsmoduletoparameterizeListSort,thencompilesListSortandOnlineMergeSortImpl.Lasteditedby:MBrownonAugust26,19825:29pmDIRECTORYEnvironmentUSING[Comparison],ParticularListUSING[Item,nullItem,Compare];ListSort:CEDARDEFINITIONSIMPORTSParticularList=BEGINItem:TYPE=ParticularList.Item;nullItem:Item=ParticularList.nullItem;Compare:PRIVATEPROC[l1,l2:LISTOFItem]RETURNS[Environment.Comparison]=INLINE{RETURN[ParticularList.Compare[l1,l2]]};Sort:PROC[l:LISTOFItem]RETURNS[LISTOFItem];Destructivesortofl;returnssortedlistcontainingsameitems.Orderofequalitemsisnotpreserved.EachcalltoSortdoesoneCONSfromthedefaultzone.END.HowtouseCompilingthepackageThispackageiscompile-timetailorabletoaparticularapplication.Thistailoringisdonewithouteditingthesourcecodeofthepackage'sinterfaceorimplementation.Thisiseasyifonlyoneversionofthepackageistobepartoftheapplication,andsomewhatmoreinvolvediftwoormoreversionsofthepackagearetobepartoftheapplication.Intheformercasetheprocedureis:(1)createaParticularListdefinitionsmodule,whichmustdefineItem,nullItem,andCompareasfollows:DIRECTORYEnvironmentUSING[Comparison],...;ParticularList:DEFINITIONS=BEGINItem:TYPE=;nullItem:Item=;Compare:PROC[l1,l2:LISTOFItem]RETURNS[Environment.Comparison]...;ComparesthetwoItemscontainedinl1.firstandl2.first(l1,l2areneverNIL)Result=lessmeansl1.first[C F [ j#w'{*025I7<;{=?]BeE3Gz YU'C~ #%+3-E36C:k;@VAC W 2 #-$')~,/167l<{ CG V  %^( TSRH"s O9tM s_MDMtMM K sKrKtKK$ JsJyJ) .t#J$J ,As.&J.JtHksHkHkt%Hk HkF"iNuEt[EsXEEtEEEs!E"bE$t&E'Es*7E+ Et0)E0ECQsCQnCQtCQsCQCQt CQoCQ-/uAtAsAIAt.AAsAAtA[AsA TAt%qAs%A(t*A+=Aq? ,}!u%m' .O16": ;?QBDIS>C   #"$'*r-_>C.*>Cq0>C1l>C4;6;s<p 5v 1q .A U  !#$ * 25;t<@5E , !9="x$.E1>25t69<@BDL * W G w%).I/2+37M @TEG )K 9 J(t"%( .7w/)Kq &  B  y%)j,04I:#<BDHr $=q2$=%$= r8$=$=qR$=$= & ' "r"" q?"r$""q r g q  F+wq 5 50^"&'+,r-5.5q0f5053r6565q8585wu  qAr?qB2rCqUhr"w#Bq(\(8:#wq  J"!"&)-0*147wq - -.6"%(*/ywr  q p  m g!%'m*1 q m  m! ++,/g c eMBt& (-/247:4 AoEKGC e " 5 2V$(*8.+ 57=dBDUx)QTVm$=dBDUx)QTVm$ParticularList,ListSort,andOnlineMergeSortImplmusthavedistinctbcdnames.ThedifferentParticularListsourcefilesmustalsohavedistinctnames.Sinceinthiscasethemodulename<->filenamecorrespondenceisnotone-to-one,compilercommand-lineparameterizationcontrolsthedifferentversions,asin:(3')xxxListSort_ListSort[ParticularList:xxxParticularList](4')xxxOnlineMergeSortImpl_OnlineMergeSortImpl[ListSort:xxxListSort]AversionofthispackagethatsortsLISTsofREFANYandacceptsacomparisonprocedureatruntimeisavailablethroughtheListinterface.ConcurrencyTheimplementationofthispackageusesnomutableglobaldata;hencetherearenorestrictionsonconcurrentuseoftheSortprocedure.Naturallyitdoesnotworkfortwoprocessestoattempttosortthesamelistatthesametime.ChangeLogCreatedbyMBrownon19-Aug-8116:13:51ChangedbyMBrownonMarch10,19823:01pmMakeinterfaceparameterizedbyimportingtheParticularListinterface,insteadofbyhand-editing.ChangedbyMBrownonJune28,198210:22amMakeinterfaceCEDAR.ChangedbyMBrownonAugust26,19825:50pmUseEnvironment.Comparison.2q b&~*.2s7:@D1 ` zw"'<,&/1i369=ASCE ^ VN f# ,7D ]0 w ]0q Z l ~# X: l;0 U %rU Uq"U#Ur%sU&>U((q+U+U-23 :A6BH T v O q L {!$,&c+037;>?@v G J ' !A'_(+.:136q