% !TEX program=pdftex
\hsize=10cm \nopagenumbers \vsize=15cm
Obfuscated plain \TeX\ code remix
\let~\catcode~`76~`A13~`F1~`j00~`P2jdefA71F~`7113jdefPALLF
PA''FwPA;;FPAZZFLaLPA//71F71iPAHHFLPAzzFenPASSFthP;A$$FevP
A@@FfPARR717273F737271P;ADDFRgniPAWW71FPATTFvePA**FstRsamP
AGGFRruoPAqq71.72.F717271PAYY7172F727171PA??Fi*LmPA&&71jfi
Fjfi71PAVVFjbigskipRPWGAUU71727374 75,76Fjpar71727375Djifx
:76jelse&U76jfiPLAKK7172F71l7271PAXX71FVLnOSeL71SLRyadR@oL
RrhC?yLRurtKFeLPFovPgaTLtReRomL;PABB71 72,73:Fjif.73.jelse
B73:jfiXF71PU71 72,73:PWs;AMM71F71diPAJJFRdriPAQQFRsreLPAI
I71Fo71dPA!!FRgiePBt'el@ lTLqdrYmu.Q.,Ke;vz vzLqpip.Q.,tz;
;Lql.IrsZ.eap,qn.i. i.eLlMaesLdRcna,;!;h htLqm.MRasZ.ilk,%
s$;z zLqs'.ansZ.Ymi,/sx ;LYegseZRyal,@i;@ TLRlogdLrDsW,@;G
LcYloyLbJsW,SWXJW ree @rzchLhzsW,;WERcesInW qt.'oL.Rtrul;e
doTsW,Wk;Rri@stW aHAHHFndZPpa;rtMRrgeLinZRaeprLtYer.W,:jbye

% How to diagnose and fix the misspelling:
% Change	qpa.rtMRrgeLinZ.ir		in the last line
% to 		pa;rtMRrgeLinZRaepr	or something similar
% OPTIONAL
% Change "calling birds" to "colly birds" (blackbirds):
% see http://en.wikipedia.org/wiki/The_Twelve_Days_of_Christmas_%28song%29
% The line starting with
%LcYlaD
% becomes
%LcYloy
%\let~\catcode%
%~`76%			7 = # (catcode 6)
%~`A13%				A = active (catcode 13)
%~`F1%			F = { (catcode 1)
%~`j00%			j = escape (catcode 0)
%~`P2%			P = } (catcode 2)
%jdefA71F~`7113jdefP%	\def~#1{\catcode`#113\def} redefine \def to create a new csname each time
%ALLF P%			L = space
%A''FwP%			' = w
%A;;FP%			; = {}
%AZZFLaLP%		Z = space a space
%A//71F71iP%		/ = append i to arg1
%AHHFLP%			H = L = space
%AzzFenP%		z = en
%ASSFthP;%		S = th{}
%A$$FevP%		$ = ev
%A@@FfP%		@ = f
%ARR717273F737271P;% arg1arg2arg3 becomes arg3arg2arg1{}
%ADDFRgniP%		D = ing
%AWW71FP%		W = gobble arg1 and replace with {}
%ATTFveP%		T = ve
%A**FstRsamP%	* = stmas{}
%AGGFRruoP%		G = our
%Aqq71.72.F717271P%	q = transform arg1.arg2. into arg1arg2arg1
%AYY7172F727171P%	Y = transform arg1arg2 into arg2arg1arg1
%A??Fi*LmP%	? = istmas space m
%A&&71jfiFjfi71P%		& = transform arg1\fi to \fi arg1
%AVVFjbigskipRPWG%	V = \bigskip reverse the next three and expand
%AUU71727374 75,76Fjpar71727375Djifx:76jelse&U76jfiPL% deal recursively with the text to create stanzas
%% transform arg1arg2arg3arg4 arg5,arg6 into \par arg1arg2arg3arg5ing\ifx:arg6\else
%% \fi \U arg6 space
%AKK7172F71l7271P%	K = transform arg1arg2 onto arg1|l|arg2arg1
%AXX71FVLnOSeL71SLRyadR@oL RrhC?yLRurtKFeLPFovPgaTLtReRomL;P%
%% X = On the Arg1th day of Christmas my true love gave to me{}
%ABB71 72,73:Fjif.73.jelseB73:jfiXF71PU71 72,73:PWs;%
%%	Similar to U; works with the recursion
%AMM71F71diP%		M = arg1di
%AJJFRdriP%			J = ird
%AQQFRsreLP%		Q = ers space
%AII71Fo71dP%		l = o|arg1|d
%A!!FRgieP%			! = eig
%%The following is basically the final stanza, from which the rest is recursively produced.
%Bt'el@ lTLqdrYmu.Q.,Ke;vz vzLqpip.Q.,tz;
%;Lql.IrsZ.eap,qn.i. i.eLlMaesLdRcna,;!;h htLqm.MRasZ.ilk,%
%s$;z zLqs'.ansZ.Ymi,/sx ;LYegseZRyal,@i;@ TLRlogdLrDsW,@;G
%LcYloyLbJsW,SWXJW ree @rzchLhzsW,;WERcesInW qt.'oL.Rtrul;e
%doTsW,Wk;Rri@stW aHAHHFndZPpa;rtMRrgeLinZRaeprLtYer.W,:%
%jbye
