Since there has not been a response (and since I am still unhappy with the limitations of \definesynonyms) I came up with my own solution which is included in this mail. The code provides a fully automated handling of symbols. I think this might be useful for a lot of people in engineering, physics, etc.. It should be more generalized and packed into a module though.

Kind regards,

Thomas

% Document Layout \setupcolors[state=start] \setuppapersize[A4][A4]

% Typography \setupwhitespace[medium] \setupindenting[no] \setupbodyfont[sans, 11pt]

% PDF Output Adjustments \setupinteraction[state=start, focus=standard, style=, click=yes, color=, contrastcolor=,]

% Units \defineunit[sunit][separator=small] \setupunit[space=medium]

\setuphead[section][style={\bfc}, before={\bigskip}, after={}]

% Lua code to set up a database of symbols \definedescription[SymItem][] \startluacode userdata = userdata or {} userdata.listofsymbols = {} -- hash table with all symbols of the form keyword:{symbol, {unit=... , description=...}}

function userdata.addsym(keyword, symbol, option) -- parses the input and adds an entry to the hash table keywords = utilities.parsers.settings_to_array(keyword) symbols = utilities.parsers.settings_to_array(symbol) options = utilities.parsers.settings_to_hash(option) userdata.listofsymbols[keywords[1]] = {symbols[1], options} end

function userdata.getsym(keyword) -- prints the symbol to a given keyword context.math(userdata.listofsymbols[keyword][1]) end

function userdata.symattr(keyword, attribute) -- prints whatever attribute of the symbol (its unit, description, ...) context(userdata.listofsymbols[keyword][2][attribute]) end

function userdata.sorttable(t,o) -- sorting algorithm: hash table gets inserted to an indexed array which then can be indexed by the iterator local a = {} for n in pairs(t) do table.insert(a, n) end if o then table.sort(a, function(a,b) return o(t, a, b) end) else table.sort(a) end local i = 0 local iterator = function () i = i + 1 return a[i], t[a[i]] end return iterator end

function userdata.placelistofsymbols() -- prints the List of Symbols greekgroup = {} latingroup = {} for keyword, values in next, userdata.listofsymbols do -- devides the symbol list into greek and latin letters if values[2]["group"] == "greek" then greekgroup[keyword] = values elseif values[2]["group"] == "latin" then latingroup[keyword] = values end end context.setuptabulate{distance="1ex"} context.starttabulate{"|lw(0.18\textwidth)|lw(0.18\textwidth)|p(0.6\textwidth)|"} context.NC() context.bf() context("Symbol") context.NC() context.bf() context("Unit") context.NC() context.bf() context("Description") context.NC() context.FR() context.HL() function printlistitem(keyword, values) context.NC() context.startSymItem({reference="sym:"..keyword, title=values[1]}) context.math(values[1]) context.stopSymItem() context.NC() context(values[2]["unit"]) context.NC() context(values[2]["description"]) context.NC() context.MR() end for keyword, values in userdata.sorttable(greekgroup, function(t,a,b) return string.lower(a) < string.lower(b) end) do -- sorting algorithm uses the "<"-comparator to compare the keys a and b printlistitem(keyword, values) end context.TB{"2ex"} for keyword, values in userdata.sorttable(latingroup, function(t,a,b) return string.lower(a) < string.lower(b) end) do printlistitem(keyword, values) end context.stoptabulate() end \stopluacode

% Create the hook to the lua functions \def\addsym[#1][#2][#3]{\ctxlua{userdata.addsym([==[#1]==], [==[#2]==], [==[#3]==])}} \def\getsym[#1]{\ctxlua{userdata.getsym([==[#1]==])}} \def\symattr[#1][#2]{\ctxlua{userdata.symattr([==[#1]==], [==[#2]==])}}

% Print a symbol with \sym[keyword]. Printed as an internal link to the entry in the List of Symbols via \goto{symbol}[sym:keyword] \def\sym[#1]{\goto{\getsym[#1]}[sym:#1]}

% Create a database containing all symbols with \addsym[keyword][symbol][options] \def\loadsymbols{ \addsym[beta][\beta][unit={\sunit{meter per second}}, description={Mass transfer coefficient}, group={greek}] \addsym[alpha][\alpha][unit={\sunit{watt per square meter per kelvin}}, description={Heat transfer coefficient}, group={greek}] \addsym[c][c][unit={\sunit{kilogram per cubic meter}}, description={Concentration}, group={latin}] \addsym[m][m][unit={\sunit{kilogram}}, description={Mass}, group={latin}] \addsym[A][A][unit={\sunit{square meter}}, description={Phase boundary interface}, group={latin}] \addsym[Q][Q][unit={\sunit{joule}}, description={Heat}, group={latin}] \addsym[T][T][unit={\sunit{kelvin}}, description={Temperature}, group={latin}] \addsym[t][t][unit={\sunit{second}}, description={Time}, group={latin}] }

% Print the List of Symbols with \placelistofsymbols \def\placelistofsymbols{\loadsymbols\ctxlua{userdata.placelistofsymbols()}}

\starttext

\startfrontmatter

\startsubject[title=Content] \placecontent \stopsubject

\startsection[title=List of Tables] \placelistoftables \stopsection

\startsection[title=List of Symbols] \placelistofsymbols \stopsection

\stopfrontmatter

\startbodymatter

\startsection[title=Symbols] \startsubsection[title=Using the Symbols] \placeformula \startsubformulas \startformula \startalign \NC \frac{d\sym[m]}{d\sym[t]} \NC = \sym[beta] \cdot \sym[A] \cdot \Delta \sym[c] \NR[eq:1] \NC \frac{d\sym[Q]}{d\sym[t]} \NC = \sym[alpha] \cdot \sym[A] \cdot \Delta \sym[T] \NR[eq:2] \stopalign \stopformula \stopsubformulas This is a reference to \in{equation}{}[eq:1] where the change of \sym[m] is calculated. \sym[beta] is called \quote{\symattr[beta][description]} and its unit is \symattr[beta][unit]. \stopsubsection \stopsection

\stopbodymatter

\stoptext

________________________________________ Von: Thomas Welter welter.thomas@outlook.de Gesendet: Mittwoch, 12. Juni 2019 17:37 An: ntg-context@ntg.nl Betreff: List of Symbols/Abbreviations/Glosses with more then two entries

The synonym "sym" defined by \definesynonyms[sym][syms][\symdesc] can take 2 entries by default:

\sym[<RefName>]{<ShortName>}{<LongName>}

For theses and whitepapers in the natural sciences and in engineering it is needed to introduce another entry for the unit:

\sym[<RefName>]{<ShortName>}{<Unit>}{<LongName>} (<-- This does of course not compile, take it as a feature request)

e.g.

\sym[Salpha]{\alpha\ }{$[W~m^{-2}~K^{-1}]$}{Heat Transfer Coefficient}

where

\sym[Salpha]{\alpha\ }{$[W~m^{-2}~K^{-1}]$ Heat Transfer Coefficient}

cannot be a good workaround since \symdesc{Salpha} should not include the unit. And of course I want the unit entry to be in a separate column when calling \placelistofsynonyms[sym]

In LaTeX I accomplished this with glossaries and glossary-mcols. Is there some neat trick to get this behaviour "the ConTeXt way" (maybe with some Lua + *.aux)?

The next step would be to define the table headers of the list of symbols such as "Symbol \NC Unit \NC Description"...

Thanks in advance and kind regards,

Thomas