Hi, Hans and list. I want to know two things. 1. If the "option/content" pair could be enabled for hashes and arrays in interfaces.definecommand: \starttext \startluacode interfaces.definecommand{ name = "acommand", --This doesn't work --arguments = {"content", "array"}, arguments = {"array"}, macro = function(t) context(table.concat(t, " and ")) end } \stopluacode %No :( %\acommand{a, b, c, d, e, f} \acommand[a, b, c, d, e, f] \stoptext 2. Is "array" available for interfaces.implement in ConTeXt MkIV? The following crashes in MkIV, but is fine with LMTX: \starttext \startluacode interfaces.implement{ name = "anothercommand", public=true, arguments = {"array"}, actions = function(t) context(table.concat(t, " and ")) end } \stopluacode \anothercommand[a, b, c, d] \stoptext I'm using MkIV as is included in the LMTX distribution. Thank you very much. Best regards, Jairo :)