Hello all, For several hours trying to find solutions of problem. My minimal example (I mention it at the end of email) for clear reasons show, that : 7 is not number. 7 is number. 7is not number. 7is not number. In the first is argument '\value' negotiable to the value, in second it is not possible (but for clear reasons too). I would need to find from argument ie macro '\\value' in the LUA function its numerical value. Is there any function that would do that? I need something as a function of context (...), which would, however, its output is not located into ConTeXt, but its result get to back to a Lua function or into variable. It is something like the expansion of an existing ConTeXt macro to its value. Thanx Jaroslav Here is my minimal example: \startluacode function test(arg) if type(arg)=='number' then context(arg.." is number.\\par ") else context(arg.." is not number.\\par") end if type(tonumber(arg))=='number' then context(arg.." is number.\\par ") else context(arg.." is not number.\\par") end end \stopluacode \starttext \def\value{7} \ctxlua{test('\value');} \blank[big] \ctxlua{test('\\value');} \stoptext