Gdddk

I have a small problem when trying to keep a key=val locally defining using xparse to pass multicols to enumerate (enumitem package). I have redefined the environment enumerate to accept the columns=number and created commands keyans[...], answer... and showanskey[...]......[...] to save the multiple choice keys and answers for worksheet exercise , all well except that when activate the columns in the first level of enumerate, affects all the levels nested in it.

When using columns=2 in the first level it looks like this:

all nested environments are in two columns.

I hope is that the output is something like this:

I tried to put group_begin: and group_end: in different places but I only get errors. The code is adapted from Defining a list environment with multiple optional arguments and MWE:

% arara: pdflatex
% arara: clean: extensions: [ aux, log] 
documentclassarticle
usepackageletltxmacro,enumitem,multicol,xparse
usepackage[most]tcolorbox
usepackage[margin=0.6in,noheadfoot,papersize=8.5in,13in]geometry % for mwe
setlengthparindent0pt
pagestyleempty

% Set keys for save-ans and save-key in enumitem
SetEnumitemKeysave-ansbefore=storecurrentid#1beginsaveanswer#1,after=endsaveanswer%
SetEnumitemKeysave-keybefore=storecurrentid#1beginsavekeyans#1,after=endsavekeyans%

% Save a copy enumerate
LetLtxMacrooldenumenumerate
LetLtxMacrooldendenumendenumerate

% Redefine enumerate for multicols
ExplSyntaxOn
RenewDocumentEnvironmentenumerate O 
 
 tl_clear:N l_keyanswer_enumitem_tl
 keys_set:nn keyanswer #1 
 int_compare:nT l_keyanswer_columns_tl > 1 
 
 setlengthmulticolsep5.0pt plus 2.0pt minus 1.5pt
 beginmulticols l_keyanswer_columns_tl 
 
 keyanswer_beginenum:V l_keyanswer_enumitem_tl 
 
 
 oldendenum
 int_compare:nT l_keyanswer_columns_tl > 1 
 endmulticols 
 
cs_new_protected:Npn keyanswer_beginenum:n #1
 oldenum[#1] 

cs_generate_variant:Nn keyanswer_beginenum:n V

tl_new:N l_keyanswer_columns_tl
tl_new:N l_keyanswer_enumitem_tl

keys_define:nn keyanswer 
 
 columns .tl_set:N = l_keyanswer_columns_tl,
 columns .initial:n = 1,
 unknown .code:n = tl_put_right:Nx l_keyanswer_enumitem_tl 
 l_keys_key_tl tl_if_empty:nF #1 = exp_not:n #1 , ,
 

% Implementation to save answer... and keyans[...] in lists
prop_new:N g_keyanswer_admin_prop

cs_new:Npn storecurrentid #1%
 prop_gput:Nnn g_keyanswer_admin_prop current-id #1
 
cs_new:Npn retrievecurrentid %
 prop_item:Nn g_keyanswer_admin_prop current-id
 

% environments for save answer... and keyans[...]
NewDocumentEnvironmentsaveanswer m %
 setlist[enumerate,2]leftmargin=16pt,nosep,itemsep=0pt,label=(alph*),before=stepdownlevel,after=stepuplevel%
 setlist[enumerate,3]leftmargin=20pt,nosep,itemsep=0pt,label=Roman*.,before=stepdownlevel,after=stepuplevel%
 seq_if_exist:cF l_keyanswer_data_#1_seq seq_new:c l_keyanswer_data_#1_seq 
 leavevmode 

NewDocumentEnvironmentsavekeyans m %
 setlist[enumerate,1]left=0pt,labelsep=5pt,itemsep=1pt,label=arabic*.%
 setlist[enumerate,2]leftmargin=16pt,nosep,label=Alph*)%
 seq_if_exist:cF l_keyanswer_data_#1_seq %
 seq_new:c l_keyanswer_data_#1_seq leavevmode 

% commands answer... and keyans[...]
NewDocumentCommandanswer +m %
 seq_gput_right:cn l_keyanswer_data_ retrievecurrentid _seq item #1
 par%
 

NewDocumentCommandkeyans !o %
 IfNoValueTF#1%
 tl_set:Nn l_tmpa_tl protectitem%
 tl_put_right:Nx l_tmpa_tl protectspace Alphenumii% 
 seq_gput_right:cV l_keyanswer_data_ retrievecurrentid _seq l_tmpa_tl%
 par%
 %
 seq_gput_right:cn l_keyanswer_data_ retrievecurrentid _seq item #1%
 par%
 %
 %

% stepdownlevel and stepuplevel for save in nested enumerate
newcommandstepdownlevel%
 seq_gput_right:cn l_keyanswer_data_ retrievecurrentid _seq item beginenumerate
 
newcommandstepuplevel%
 seq_gput_right:cn l_keyanswer_data_ retrievecurrentid _seq endenumerate
 

% Display answer... and keyans[...] in list by id
cs_new:Npn displayseqcontent #1#2 %
 seq_if_empty:cF l_keyanswer_data_#1_seq %
 seq_log:c l_keyanswer_data_#1_seq 
 setlist[enumerate,1]labelsep=5pt,label=arabic*.,leftmargin=15pt,labelsep=3pt,font=footnotesize,nosep,widest=80%
 setlist[enumerate,2]font=footnotesize,labelsep=5pt,leftmargin=0.6cm,nosep,label=(alph*)%
 setlist[enumerate,3]font=footnotesize,labelsep=5pt,leftmargin=0.3cm,nosep,label=Roman*.%
 beginenumerate[#2] smallsetlengthcolumnsep0pt
 seq_map_inline:cn l_keyanswer_data_#1_seq ##1 
 endenumerate
 
 
ExplSyntaxOff

% showanskey[tcolorbox]titlelist ref[columns]
DeclareTotalTColorBoxshowanskeyO m m O4
 colback=white,size=small,top=0mm,bottom=1.5mm, left=0mm,width=columnwidth,title filled,%
 fontupper=small,fonttitle=smallsffamily, adjusted title=#2,center title,#1
 displayseqcontent#3columns=#4 %

begindocument

sectionMultiple Choice

beginenumerate[save-key=mchoice,left=0pt,columns=2]
item First type of questions
 beginenumerate
 item value 
 item value 
 item value
 item correct keyans
 item value 
 endenumerate
item Second type of questions
 beginenumerate[leftmargin=2pc,label=Roman*.]
 item $2alpha+2delta=90^circ$
 item $alpha=delta$ 
 item $angle EDF=45^circ$
 endenumerate
beginenumerate[columns=2]% 
 item I only 
 item II only keyans
 item I and II only
 item I and III only 
 item I, II, and III
endenumerate
%columnbreak % 
item Third type of questions
 beginenumerate[leftmargin=2pc,label=(arabic*)]
 item $2alpha+2delta=90^circ$
 item $angle EDF=45^circ$
 endenumerate
 beginenumerate
 item Altenativa A 
 item Altenativa B 
 item Altenativa C keyans
 item Altenativa D
 item Altenativa E 
 endenumerate
item Fourth type of question, a problem with numerical response keyans[$sqrt2$]

endenumerate

sectionWorksheet

beginenumerate[save-ans=Worksheet,left=0pt,labelsep=5pt,nosep,label=arabic*.,columns=2]
item Factor $x^2-2x+1$ answer$left(x-1right)^2$ 
item Factor $3x+3y+3z$ answer$3(x+y+z)$
item True False
 beginenumerate
 item $alpha > delta$ answerFalse
 item LaTeX2e is cool? answerVery True!
 endenumerate 
item Related to Linux
 beginenumerate
 item You use linux? answerYes
 item Usually uses the package manager? answerYes
 item Rate the following package managers
 beginenumerate
 item dnf answergood
 item apt answervery good
 item yum answerobsolete
 endenumerate
 endenumerate 
endenumerate

sectionAnswers
showanskey[colback=yellow!30!white]Multiple Choice Keysmchoice[5]
showanskey[colback=yellow!30!white]Solution WorksheetWorksheet[2]

sectionNormal enumerate
beginenumerate
item First level
 beginenumerate
 item Second level 
 item value 
 item beginenumerate
 item Third level
 item value
 endenumerate
 endenumerate
endenumerate

enddocument

If put in all sublevels columns=1 skip the problem, but, can't do this with showanskey. If instead of using RenewDocumentEnvironmentenumerate I use directly

SetEnumitemKeycolumnsbefore=beginmulticols#1,after=endmulticols%

I get the following error:

! LaTeX3 Error: Variable l_keyanswer_data_mchoice_seq undefined.

How can i fix this?

Grateful

Once you set the keys, the values remain as stated.

You can simply restore a value by specifying the relevant key, before setting the specified ones:

keys_set:nn keyanswer #1 

should become

keys_set:nn keyanswer columns=1, #1