Module:Xswitch

This module is a pretty haphazard implementation of a discussed Lua request. (yes, you can do better than this) It takes an input number or string (the first numbered parameter) and sorts it back through the thresholds it is given until it finds one that it is greater than - then it spits out that result. The thresholds and results are given either as parameters or as a file. For example:

{{#invoke:xswitch|main
|profile={{some file}}
|type=string
|ant
|astronaut|astronaut
|Cherry|Cherry
|Apple|Apple
|cosmonaut|cosmonaut
|camper|camper
}}

will take the profile from "some file" that you've transcluded, ignoring everything after "ant". But if the profile were omitted, it would return "Apple" because that is the first thing working backwards that it is greater than. If you want smarter behavior than that, sort your parameters. :)

The file to accomplish the same tests would read

|astronaut|astronaut
|Cherry|Cherry
|Apple|Apple
|cosmonaut|cosmonaut
|camper|camper

The idea is/was that for a very long set of tests you might want to put them all in a file to edit, so you don't have to pass them all in the template each time and can edit them in one place.

Setting type to anything forces a string comparison - otherwise a numeric comparison is forced.

---

p = {}

function extractprofile(profile, type)
 -- takes a profile like [[Templates:xswitch/test-profile]] and extracts the levels and results, _instead_ of having them passed as parameters

   local x = 0
   local pattern = {}
   local mins = {}
   local results = {}
   for min,result in mw.ustring.gmatch(profile, "(.-)|(.-)\n") do
      if min then
         if type then
         	min = tostring(min)
         else
         	min = tonumber(min)
         end -- and I have nofklu WHAT this does to Unicode, sorry!  Tostring is supposedly not necessary but I am suspicious.
         table.insert(mins, min)
         table.insert(results, (result or ""))
      end
   end
   return mins,results
end

function p.main(frame)
   local args = frame.args
   local parent, pargs, type, profile, input, number
   if frame.getparent then 
       parent = frame:getparent()
       pargs = parent.args
       type = pargs.type
       input = pargs[1]
   end -- I have nofklu why this gives me an error this time.  Say who what?
   type = type or args.type or nil -- sort as number or string.  Default to number (nil), think.
   profile = profile or args.profile or nil -- File to transclude to obtain the thresholds
   input = input or args[1] or ""
   if type then input = tostring(input) else input = tonumber(input) end
   local mins = {}
   local results = {}
   if profile then
   	  mins,results = extractprofile(profile, type)
   	  number=table.maxn(mins)
   end
   if not(mins[1]) then -- (no profile or profile extraction unsuccessful)
      mins={}; results={} -- suspicious mind...
      number = 0
      repeat
         number = number + 1
         local min
         if parent then min = pargs[number * 2]; result = pargs[number * 2 + 1] else min = nil; result = nil end
         min = min or args[number * 2] or nil -- numbered params from 2 on alternate as threshold and result
         local result = result or args[number*2+1] or ""
         if min then
            if type then
            	min = tostring(min)
            else
            	min = tonumber(min)
            end
            table.insert(mins, min)
            table.insert(results, (result or ""))
         end
      until not(mins[number])
   end
   local toolow = results[number - 1] or ""
   while number > 1 do
      number = number-1
      if input > mins[number] then
      	output = results[number];
      	break
      end
   end

   return (output or toolow or "")

end

return p

This module "Xswitch" is from Wikipedia if otherwise notified