metalua/extension/log.mlua

-------------------------------------------------------------------------------
-- Copyright (c) 2006-2013 Fabien Fleutot and others.
--
-- All rights reserved.
--
-- This program and the accompanying materials are made available
-- under the terms of the Eclipse Public License v1.0 which
-- accompanies this distribution, and is available at
-- http://www.eclipse.org/legal/epl-v10.html
--
-- This program and the accompanying materials are also made available
-- under the terms of the MIT public license which accompanies this
-- distribution, and is available at http://www.lua.org/license.html
--
-- Contributors:
--     Fabien Fleutot - API and implementation
--
-------------------------------------------------------------------------------

require 'metalua.dollar'

-{ extension ('match', ...) }

function dollar.log(...)
   local args   = {...}
   local ti     = table.insert
   local code   = { }
   local nohash = false
   local width  = 80

   local i=1
   if args[i].tag=='String' then
      ti(code, +{print(" [LOG] "..-{args[1]})})
      i += 1
   end

   local xtra_args, names, vals = { }, { }, { }
   for i=i, #args do
      match args[i] with
      | +{ 'nohash' } -> nohash = true
      | `Number{ w }  -> width = w
      --| `String{...} | `Number{...} -> ti (xtra_args, args[i])
      | `Id{n} -> ti (names, n); ti (vals, args[i])
      | x      -> ti (names, table.tostring(x, 'nohash')); ti (vals, x)
      end
   end

   for i=1, #names do
      local msg = string.format(" [LOG] %s = ", names[i])
      local printer = `Call{ +{table.tostring},
                              vals[i],
                              `Number{ width },
                              `Number{ #msg  } }
      if nohash then ti(printer, +{'nohash'}) end
      ti (code, `Call{ +{printf}, +{"%s%s"}, `String{ msg }, printer })
   end
   return code
end

return function() end