; TeX output 1997.01.23:0049soDtGGcmr17The7tGGcmss17hhlinepacqkage!", cmsy10XQ cmr12DarvidCarlislepScarlisle@cs.man.ac.uk&37 1994/05/23.!Kt : cmbx9AbstractэoߤN cmtt9\hhlineיo cmr9proAducesalinelik9e\hline,oradoublelinelike\hline\hline, bexceptTforitsin9teractionwithverticallines.!čINff cmbx121aLIntros3ductionIK`y cmr10Theargumentto O>G`!`!::::fd#  rfda@b  Uc꬟ f!d  #8:ɟ:ɍ:::`!q[#  rfd1@2  Ua3 f>4  #8:ɟ:ɍ::`!`!`!::#  fdiAj  U>k gl㏟  #8䎍:Ʉ:O>G`!:#  fdw@Wx  U>y g[z:  #8:ɟ:ɍ::::O>O>G`!`!::::YXThe linesproGducedbyL5ffٓRcmr7A͉TU>'ExX's\hlineconsistofasingle(TU>'EXprimitive) I\hrule.tThe4linesproGducedby\hhlinearemadeupoflotsofsmalllineseg-Iments.IZTU>'ExX willplacetheseveryaccuratelyinthe.dvi le,NbuttheprogramthatIyoukusetoprintthe.dvi lemaynotlineupthesesegmentsexactly*.(AksimilarIproblemUUcanoGccurwithdiagonallinesinthepictureenvironment.)XIfthise ectcausesaproblem,youcouldtryadi erentdriverprogram,orifIthisUUisnotpGossible,increasing\arrayrulewidthmayhelptoreducethee ect.!čI2aLTheffMacrosLs1S" cmsy9h#ow cmss9pack9age#g i3P\HH@boxIMakesabGoxcontainingadoublehlinesegment.ˑThemostcommoncase,PbGothIrulesoflength\doublerulesepwillbGestoredin\box1,thisisnotinitialiseduntilI\hhline*iscalledastheusermaychangetheparameters\doublerulesepandI\arrayrulewidth.nThertwoargumentsto\HH@boxarethewidths(ielengths)ofItheUUtopandbGottomrules.Ls2S\def\HH@box#1#2{\vbox{% Ls3]\hrule\@height\arrayrulewidth\@width#1Ls4]\vskip\doublerulesepLs5]\hrule\@height\arrayrulewidth\@width#2}}3P\HH@addIBuildUUupthepreambleintheregister\toks@.Ls6S\def\HH@add#1{\toks@\expandafter{\the\toks@#1}} L\HH@xexpast L\HH@xexnoopIW*e~`bGorrow'theversionof\@xexpastfromMittelbach'sarray*.sty,as~thisallows I#UUtoappGearintheargumentlist.Ls7S\def\HH@xexpast#1*#2#3#4\@@{% Ls8ap\@tempcnta#2Ls9ap\toks@={#1}\@temptokena={#3}%I10ap\let\the@toksz\relax\let\the@toks\relaxI11ap\def\@tempa{\the@toksz}%I12ap\ifnum\@tempcnta>0\@whilenum\@tempcnta>0\doI13kJ{\edef\@tempa{\@tempa\the@toks}\advance\@tempcnta\m@ne}%I14t\let\@tempb\HH@xexpast\elseI15t\let\@tempb\HH@xexnoop\fi2 soI16ap\def\the@toksz{\the\toks@}\def\the@toks{\the\@temptokena}% I17ap\edef\@tempa{\@tempa}%I18ap\expandafter\@tempb\@tempa#4\@@}I19I20S\def\HH@xexnoop#1\@@{}3P\hhlineIUseDasimpli edversionof\@mkpreamtobreakaparttheargumentto\hhline. IActuallyitisoversimpli ed,