\def\sdef#1{\expandafter\def\csname#1\endcsname}
\def\slet#1#2{\expandafter\let\csname#1\expandafter\endcsname\csname#2\endcsname}
+% Assign a control sequence given as a string, complain if it is not defined.
+\def\sget#1#2{\ifcsname#2\endcsname
+ \expandafter\let\expandafter#1\csname#2\endcsname
+ \else
+ \errmessage{Undefined control sequence #2}%
+ \let#1\relax
+ \fi
+}
+
% Add \protected to an existing macro
\def\addprotected#1{\protected\edef#1{\expandafter\unexpanded\expandafter{#1}}}
% Usage:
%
+% \list{style}
+% \:first item
+% \:second item
+% \endlist
+%
+% Available styles (others can be defined by \sdef{item:<style>}{<marker>})
+%
+% o % bullet
+% O % empty circle
+% * % asterisk
+% - % en-dash
+% . % dot
+% n % 1, 2, 3
+% i % i, ii, iii
+% I % I, II, III
+% a % a, b, c
+% A % A, B, C
+% g % α, β, γ
+%
+% Meta-styles (can be used to modify an arbitrary style, currently hard-wired)
+%
+% #. % with a dot behind
+% #) % with a parenthesis behind
+% (#) % enclosed in parentheses
+%
+% Historic usage:
+%
% \itemize\ibull % or other marker
% \:first item
% \:second item
\def\inititemize{\begingroup\preitemize\itemstrue\parindent=0pt}
-\def\itemize#1{\inititemize\setbox\itembox\llap{#1\hskip\itemmarkerskip}%
-\let\:=\singleitem}
+\def\list#1{\inititemize\itemcount=0\liststyle{#1}\let\:=\listitem}
+\def\listitem{\par\leavevmode\advance\itemcount by 1
+ \llap{\listmarker\hskip\itemmarkerskip}\ignorespaces}
-\def\singleitem{\par\leavevmode\copy\itembox\ignorespaces}
+\def\liststyle#1{%
+ \edef\markertmp{#1}
+ \ifcsname item:\markertmp\endcsname
+ \sget\listmarker{item:\markertmp}%
+ \else
+ \sget\listmarker{metaitem:\markertometa#1^^X}%
+ \sget\markerinner{item:\markertoinner#1^^X}%
+ \fi
+}
+
+\def\markertometa#1{%
+ \ifx#1^^X%
+ \else
+ \ifx#1((%
+ \else\ifx#1))%
+ \else\ifx#1..%
+ \else=%
+ \fi\fi\fi
+ \expandafter\markertometa
+ \fi
+}
+
+\def\markertoinner#1{%
+ \ifx#1^^X%
+ \else
+ \ifx#1(%
+ \else\ifx#1)%
+ \else\ifx#1.%
+ \else#1%
+ \fi\fi\fi
+ \expandafter\markertoinner
+ \fi
+}
\def\endlist{\par\endgroup\postitemize}
-% Markers for \itemize
-\def\ibull{\raise0.2ex\hbox{$\bullet$}}
-\def\idot{\raise0.2ex\hbox{$\cdot$}}
-\def\istar{\raise0.2ex\hbox{$\ast$}}
+% List styles
+\sdef{item:o}{\raise0.2ex\hbox{$\bullet$}}
+\sdef{item:O}{\raise0.2ex\hbox{$\circ$}}
+\sdef{item:*}{\raise0.2ex\hbox{$\ast$}}
+\sdef{item:-}{--}
+\sdef{item:.}{\raise0.2ex\hbox{$\cdot$}}
+\sdef{item:n}{\the\itemcount}
+\sdef{item:i}{\romannumeral\itemcount}
+\sdef{item:I}{\uppercase\expandafter{\romannumeral\itemcount}}
+\sdef{item:a}{\char\numexpr 96+\itemcount\relax}
+\sdef{item:A}{\char\numexpr 64+\itemcount\relax}
+\sdef{item:g}{$\ifcase\itemcount\or\alpha\or\beta\or\gamma\or\delta\or\epsilon\or
+\zeta\or\eta\or\theta\or\iota\or\kappa\or\lambda\or\mu\or\nu\or\xi\or\pi\or\rho
+\or\sigma\or\tau\or\upsilon\or\phi\or\chi\or\psi\or\omega\fi$}
+
+% List meta-styles
+\sdef{metaitem:=.}{\markerinner.}
+\sdef{metaitem:=)}{\markerinner)}
+\sdef{metaitem:(=)}{(\markerinner)}
+
+% Old-style lists
+
+\def\itemize#1{\inititemize\setbox\itembox\llap{#1\hskip\itemmarkerskip}%
+\let\:=\singleitem}
+
+\def\singleitem{\par\leavevmode\copy\itembox\ignorespaces}
\def\numlist#1{\inititemize\itemcount=0\let\:=\numbereditem
\let\itemnumbering=#1}
\def\numbereditem{\par\leavevmode\advance\itemcount by 1
\llap{\itemnumbering\hskip\itemmarkerskip}\ignorespaces}
-% Numbering styles for \numlist
+% Old-style markers
+
+\def\ibull{\raise0.2ex\hbox{$\bullet$}}
+\def\idot{\raise0.2ex\hbox{$\cdot$}}
+\def\istar{\raise0.2ex\hbox{$\ast$}}
+
\def\nnorm{\the\itemcount}
\def\ndotted{\nnorm.}
\def\nparen{\nnorm)}