Re: [NTG-context] Tabulator in database file not passed to Lua

23 Jan 2014


      On 1/23/2014 9:43 PM, Joshua Krämer wrote:
...
Dear list,
I use the database module to load the lines of a file with some
data.  The lines are then separated with a lua script.  I use lua,
because I need to do some other things with the data (rounding
numbers, combining some fields etc.)  Please consider the following
minimal working example:
\usemodule[database]
\defineseparatedlist [Data]
[
  before=,
  after=,
  separator={},
  commentchar=\letterpercent,
  command=\Tabrow,
]
\startluacode
function explode(sep,str)
if (sep=="") then return false end
   local pos,arr = 0,{}
   -- for each separator found
   for st,sp in function() return string.find(str,sep,pos,true) end do
     -- Attach chars left of current separator
     table.insert(arr,string.sub(str,pos,st-1))
     -- Jump past current separator
     pos = sp + 1
   end
   -- Attach chars right of last separator
   table.insert(arr,string.sub(str,pos))
return arr
end
function tabrow(fileline)
  local tabarray = explode(";",fileline)
  local tabline = ""
  for index,value in ipairs(tabarray) do
      tabline = tabline .. " / " .. value
  end
  return tabline
end
\stopluacode
\define[1]\Tabrow{\ctxlua{context(tabrow("#1"))}}
\starttext
\processseparatedfile[Data][Test.dat]
\stoptext
This is the content of the file Test.dat:
Eins;zwei;drei;vier
Of course the line separation could be done easier with the database
module.  However, I thought this way I could use the tabulator as the
separator in my file.  But when I change the separator from ";" to
"\\t", it doesn't work.  I suppose this is because the tabulators are
passed to Lua as spaces.  Or is "\\t" the wrong code?  Would it be
possible to use tabulators as separators, if I load the file with lua
and not with the database module?
\starttext

\startluacode

     local f = io.open("test.dat")

     for line in f:lines() do
         local t = string.split(line,";") -- or "\t" for tabs
         context("% /t",t) -- context(table.concat(t," / ")
         context.par()
     end

\stopluacode

\stoptext


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