-- alphanum.lua (C) Andre Bogus
--[[ based on the python version of ned batchelder
Distributed under same license as original

This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or any later version.

This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
]]

-- split a string into a table of number and string values
function splitbynum(s)
       local result = {}
       for x, y in (s or ""):gmatch("(%d*)(%D*)") do
               if x ~= "" then table.insert(result, tonumber(x)) end
               if y ~= "" then table.insert(result, y) end
       end
       return result
end

-- compare two strings
function alnumcomp(x, y)
       local xt, yt = splitbynum(x), splitbynum(y)
       for i = 1, math.min(#xt, #yt) do
               local xe, ye = xt[i], yt[i]
               if type(xe) == "string" then ye = tostring(ye)
               elseif type(ye) == "string" then xe = tostring(xe) end
               if xe ~= ye then return xe < ye end
       end
       return #xt < #yt
end

-- sort a given table of strings the way humans would expect
function sortnicely(t)
               return table.sort(t, alnumcomp)
end

unsorted = {"1000X Radonius Maximus","10X Radonius","200X Radonius","20X Radonius","20X Radonius Prime","30X Radonius","40X Radonius","Allegia 50 Clasteron","Allegia 500 Clasteron","Allegia 51 Clasteron","Allegia 51B Clasteron","Allegia 52 Clasteron","Allegia 60 Clasteron","Alpha 100","Alpha 2","Alpha 200","Alpha 2A","Alpha 2A-8000","Alpha 2A-900","Callisto Morphamax","Callisto Morphamax 500","Callisto Morphamax 5000","Callisto Morphamax 600","Callisto Morphamax 700","Callisto Morphamax 7000","Callisto Morphamax 7000 SE","Callisto Morphamax 7000 SE2","QRS-60 Intrinsia Machine","QRS-60F Intrinsia Machine","QRS-62 Intrinsia Machine","QRS-62F Intrinsia Machine","Xiph Xlater 10000","Xiph Xlater 2000","Xiph Xlater 300","Xiph Xlater 40","Xiph Xlater 5","Xiph Xlater 50","Xiph Xlater 500","Xiph Xlater 5000","Xiph Xlater 58"}

sortnicely(unsorted)
for _, s in ipairs(unsorted) do print(s) end