Ipelet that allows incrementing and decrementing numeric labels (written by Tim Ophelders)

increment.lua

label = "Increment"

about = [[
Increment the first numerical value in selected text objects.
]]

function foo(model,num)
  local f
  if num == 1 then
    f = function (v) return v+1 end
  elseif num == 2 then
    f = function (v) return v-1 end
  end
  local t = { label = label,
        pno = model.pno,
        vno = model.vno,
        original = model:page():clone(),
        final = model:page():clone(),
        undo = _G.revertOriginal,
        redo = _G.revertFinal,
      }
  for i,obj,sel,layer in t.final:objects() do
    if sel and obj:type() == "text" then
      local text = obj:text()
      local a = string.match(text,"-?%d+")
      if a ~= nil then
        obj:setText(string.gsub(text,a,string.format('%d',f(tonumber(a))),1))
      end
    end
  end
  model:register(t)
end

----------------------------------------------------------------------

methods = {
   { label = "Increment", run=foo },
   { label = "Decrement", run=foo },
}

shortcuts.ipelet_1_increment = "Alt+PgUp"
shortcuts.ipelet_2_increment = "Alt+PgDown"