-- awkward 0.00
-- GCW 29/06/05
-- pseudo_awk interpreter

do
printf = function (...)
         print(string.format(unpack(arg)))
         end

-- use as: for i,field in split(text,pat) do ... end
split = function (t,p)
        local pat,n,count,L = "(.-)"..p, 1,0,string.len(t)
        local f = function (s,v)
                  local i,j,x = string.find(s,pat,n)
                  if i then
                    count = count + 1
                    n = j + 1
                    return count,x
                  elseif n < L then
                    count = count + 1
                    x = string.sub(s,n,-1)
                    n = L + 1
                    return count,x
                  end -- if
                  end -- function
        return f,t,n
        end -- function

readfile = function (name)
 local f = assert(io.open(name,"r"),"Cannot open file")
 local s = f:read("*all")
 f:close()
 return s
 end -- function

local parse = function (fn)
        local s = "\n"..readfile(fn)
        local pat = "\n(.-)(%b{})"
        RULES = {}
        for p,a in string.gfind(s,pat) do
          if p == "" then p = "true" end -- if
          local i,j,x = string.find(p,"^%s*/([^/]+)/%s*$")
          if i then p = [[string.find($[0],"]]..x..[[") ~= nil]] end
          if string.find(p,"^%s*BEGIN%s*$") then
            BEGIN = loadstring(string.sub(a,2,-2))
          elseif string.find(p,"^%s*END%s$") then
            END = loadstring(string.sub(a,2,-2))
          else
           table.insert(RULES,{
              pat = loadstring("return "..p);
              act = loadstring(string.sub(a,2,-2)); })
           end -- if
        end -- for
        end -- function
        
local awk = function(script,name)
      parse(script)
      local s = readfile(name)
      FILENAME = name
      if BEGIN then BEGIN() end -- if
      for $n,$0 in split(s,RS or "\n") do
        $,NR = {},$n
        $[0] = $0
        for i,field in split($0,FS or "%s+") do
          table.insert($,field)
        end -- for
        NF = table.getn($)
        for _,x in ipairs(RULES) do
          if x.pat() then x.act() end -- if
        end -- for
      end -- for
      if END then END() end -- if
      end -- function

awk(arg[1],arg[2])
end -- do