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Am 05.01.2012 um 15:49 schrieb Wagner Macedo:
Hello,
I'm relatively quite new to TeX world. This is my first message to list. I hope you understand me, English isn't my mother language.
I'm trying to use a variable set by \setvariable in Lua. I tried some combinations, based on manual but I couldn't succeed. The code below exemplifies what I wanted to do.
\starttext \setvariable{namespace}{var}{Some context} \ctxlua{ local s = context.getvariable("namespace", "var")
if s == "" then ... else ... end } \stoptext
I know that I can use some of \if* TeX commands, but coding in Lua is better to me.
What you’re trying is not possible but there are other ways to check the content of the variable in Lua. \startluacode userdata = userdata or { } function userdata.checkvariable(variable) if variable == "" then context("EMPTY") else context("NOT EMPTY") end end \stopluacode \setvariable{wagner}{name}{Wagner Macedo} \starttext \ctxlua{userdata.checkvariable("\getvariable{wagner}{name}")} % This does only with \startlua or \ctxlua \startlua local name = "\getvariable{wagner}{name}" if name == "" then context("No Text") else name = "Name: " .. name context(name) end \stoplua \stoptext A different method is to save the \setvariables entries in a Lua table and check the entries of the table. \startluacode userdata = userdata or { } userdata.macedo = userdata.macedo or { } userdata.macedo.data = { } function userdata.macedo.savevariables(variables) userdata.macedo.data = variables end function userdata.macedo.checkvariables() local variables = userdata.macedo.data -- check for name if variables.name == "" then context("Name: No name set") context.par() else context("Name: "..variables.name) context.par() end -- check for address if variables.address == "" then context("Address: No address set") context.par() else context("Address: "..variables.address) context.par() end end \stopluacode \starttexdefinition SaveVariables \startlua userdata.macedo.savevariables{ name = "\getvariable{macedo}{name}", address = "\getvariable{macedo}{address}", } \stoplua \stoptexdefinition \setvariables[macedo][set=\SaveVariables] \starttext \setvariables[macedo][name=Wagner Macedo] \ctxlua{userdata.macedo.checkvariables()} \setvariables[macedo][address=Secret] \ctxlua{userdata.macedo.checkvariables()} \stoptext Wolfgang