Hello, I need to check within Lua. My sample cases are very minimalistic - I'm working on more complicated task actually, where check-for-control-sequence-existence need to be performed run-time within Lua scope. Best, Lukas ---------- Původní e-mail ---------- Od: Hans van der Meer Komu: NTG ConTeXt Datum: 18. 6. 2020 12:25:42 Předmět: Re: [NTG-context] Checking existence of a macro (control sequence) by Lua - problem after updating MkIV " Why can you not simply use one of the doifundefined macro's? Something for example: \doifundefined{ExitStatus}{\gdef\ExitStatus{0}} % default to ok as in UNIX dr. Hans van der Meer " On 18 Jun 2020, at 10:27, Lukas/ConTeXt wrote: Hello, I'm using Hans' macro suggested some time before. I've just updated Ctx MkIV and my sample code: ---- \starttext  \def\MyMacro{Ahoj}  \def\MyMacWithPars#1#2{Something}  \def\Undefined{}  \let\Undefined\undefined  \def\DoNothing{}  \let\DoNothing\donothing  \startluacode    if CONTEXTLMTXMODE == 0 then        local d = tokens.defined        local c = tokens.create        function tokens.defined(s,b)            if b then                return d(s)            else                return c(s).cmd_name == "undefined_cmd"            end        end    end    --    local defined = tokens.defined    for _, v in ipairs{ "MyMacro", "MyMacWithPars", "Undefined", "DoNothing", "NonExisting" } do      print(string.format("\letterpercent-12s", v), defined(v), defined(v, true), defined(v, false))    end  \stopluacode  Aaa \stoptext ---- gives: " MyMacro         false   false   false MyMacWithPars   false   false   false Undefined       false   false   false DoNothing       false   false   false NonExisting     false   false   false " IOW, I'm not able to determine whether a control sequence has not been defined (or has \undefined value) or not. Am I doing a trivial mistake or has anything changed? Thank you for patience... Lukas________________________ ___________________________________________________________ If your question is of interest to others as well, please add an entry to the Wiki! maillist : ntg-context@ntg.nl(mailto:ntg-context@ntg.nl) / http://www.ntg. nl/mailman/listinfo/ntg-context (http://www.ntg.nl/mailman/listinfo/ntg-context) webpage  : http://www.pragma-ade.nl(http://www.pragma-ade.nl) / http:// context.aanhet.net(http://context.aanhet.net) archive  : https://bitbucket.org/phg/context-mirror/commits/ (https://bitbucket.org/phg/context-mirror/commits/) wiki     : http://contextgarden.net(http://contextgarden.net) ____________________________________________________________________________ _______ " ____________________________________________________________________________ _______ If your question is of interest to others as well, please add an entry to the Wiki! maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg- context webpage : http://www.pragma-ade.nl / http://context.aanhet.net archive : https://bitbucket.org/phg/context-mirror/commits/ wiki : http://contextgarden.net ____________________________________________________________________________ _______ "

Hello Hans, ---------- Původní e-mail ---------- { Od: Hans Hagen as you updated, it's just: \startluacode local defined = tokens.defined for _, v in ipairs{ "MyMacro", "MyMacWithPars", "Undefined", "DoNothing", "NonExisting" } do print(string.format("\letterpercent-12s", v), defined(v), defined(v, true), defined(v, false)) end \stopluacode ---------- Původní e-mail ---------- } your solution gives me: " MyMacro false true false MyMacWithPars false true false Undefined false true false DoNothing false true false NonExisting false false false " which desn't recognize \Undefined - it should give 'false' in the 2nd column of results, like \NonExisting does. But I have another solution (asked in Czech TUG) - use of 'token.get_meaning(cs)': ---- \startluacode for _, v in ipairs{ "MyMacro", "MyMacWithPars", "Undefined", "DoNothing", "NonExisting" } do print(string.format("\letterpercent-12s", v), "get_meaning", token.get_meaning(v) or "(non-existing/undefined)") end \stopluacode ---- - Produces: " MyMacro get_meaning ->Ahoj MyMacWithPars get_meaning #1#2->Something Undefined get_meaning (non-existing/undefined) DoNothing get_meaning -> NonExisting get_meaning (non-existing/undefined) " which is perfectly what I need. But thank you anyway for your effort. Best regards, Lukas