Weird error: opts[(r)-e]: parameter not set

[Sebastian Gniazdowski <psprint@xxxxxxxxxxxx>]

Hello,
I do:
    local -a opts
    zparseopts -a opts -D ${(s::):-eLdgabsTtm}

    if [[ "${#opts[@]}" -eq 0 || ( "${#opts[@]}" -eq 1 &&
    "${opts[(r)-e]}" = "-e" ) ]]; then

and this at one user setup results in error:

functionname:12: opts[(r)-e]: parameter not set

Line number points to the if. Having set -u is capable of generating
such error, however not in this case, as there is `local -a opts`. What
else can do this?

-- 
  Sebastian Gniazdowski
  psprint@xxxxxxxxxxxx