I'm trying to produce a document with several authors, using macros for
comma separated lists. My MWE is as follows:

%%%%%%%%%%%%%%%%%%%%%%
\def\autores{%
  {Luis David Gómez-Méndez, Ph. D.},
  {Adriana del Pilar Pulido-Villamarín, M. Sc.},
  {Rubiela Castañeda-Salazar, M. Sc.},
  {Juan Carlos Ulloa-Rubiano, Ph. D.},
  {Adriana Matiz-Villamil, M. Sc.}%
}

\def\lastAutor{Fidson Juarismy Vesga-Pérez, Ph. D}

\def\autorParaLista#1{#1;\space}
\def\listaAutores{\processcommacommand[\autores]\autorParaLista &
\lastAutor: autores.}

\starttext

\listaAutores

\stoptext
%%%%%%%%%%%%%%%%%%%%%%%

So far, no luck trying to extract the last item from a comma separated
list. That's the reason I created a "\lastAutor" macro, so I can treat the
last one differently.

This produces:

%%%%%%
Luis David Gómez-Méndez, Ph.D.; Adriana del Pilar Pulido-Villamarín, M.
Sc.; Rubiela Castañeda-Salazar, M. Sc.; Juan Carlos Ulloa-Rubiano, Ph.D.;
Adriana Matiz-Villamil, M. Sc.; & Fidson Juarismy Vesga-Pérez, Ph.D:
autores.
%%%%%%

However, what I'm trying to get is:

%%%%%%
Luis David Gómez-Méndez, Ph.D.; Adriana del Pilar Pulido-Villamarín, M.
Sc.; Rubiela Castañeda-Salazar, M. Sc.; Juan Carlos Ulloa-Rubiano, Ph.D.;
Adriana Matiz-Villamil, M. Sc. & Fidson Juarismy Vesga-Pérez, Ph.D: autores.
%%%%%%

Which is very close to what I need, except the ";" just before the "&". So
the question is: is it possible to do this in a more effective or simpler,
or better way, and write a macro that outputs something like "Author1;
Author2; Author3 & Author4: authors.", given a comma separated list of
authors?

-- 
Andrés Conrado Montoya
Andi Kú
andresconrado@gmail.com
http://sesentaycuatro.com
http://messier87.com
http://chiquitico.org
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