sketches/pp.lua

   1
   2 require "data_structures"
   3
   4 function serialize(o, maxdepth, indent, s)
   5   local seen = s or Stack:new()
   6   local t = type(o)
   7   local new_max_depth
   8   if maxdepth then new_max_depth = maxdepth-1 end
   9   if new_max_depth == 0 then return "<too deep>" end
  10
  11   if t == "table" and seen:contains(o) then
  12     return "..."
  13   else
  14     seen:push(o)
  15   end
  16
  17   if indent and type(indent) ~= "string" then
  18     indent = ""
  19   end
  20
  21   local result
  22
  23   if t == "string" then
  24     result = string.format("%q", o)
  25   elseif t == "table" and o.__index == o then
  26     result = string.format("Class: %q", o.name)
  27   elseif t == "table" and not (o.class and o.class.__tostring) then
  28     local nestedIndent
  29     if indent then
  30       nestedIndent = indent .. "  "
  31     end
  32
  33     result = "{"
  34     if nestedIndent then result = result .. "\n" .. nestedIndent end
  35     local nextIndex = 1
  36     local first = true
  37     for k, v in pairs(o) do
  38       if first then
  39         first = false
  40       else
  41         result = result .. ", "
  42         if nestedIndent then result = result .. "\n" .. nestedIndent end
  43       end
  44       if type(k) == "number" and k == nextIndex then
  45         nextIndex = nextIndex + 1
  46       else
  47         if type(k) == "string" and string.find(k, "^[_%a][_%w]*$") then
  48           result = result .. k
  49         else
  50           result = result .. "[" .. serialize(k, new_max_depth, nil, seen) .. "]"
  51         end
  52         result = result .. " = "
  53       end
  54       result = result .. serialize(v, new_max_depth, nestedIndent, seen)
  55     end
  56     if indent then
  57       result = result .. "\n" .. indent
  58     end
  59     result = result .. "}"
  60   else
  61     result = tostring(o)
  62   end
  63
  64   seen:pop()
  65   return result
  66 end
  67