turtleLib: A core set of tool libraries for ComputerCraft turtles

turtleLib.lua

-- turtleLib: A core set of tool libraries for ComputerCraft turtles
-- by Alexander "SquidLord" Williams (SaladinVrai)

-- Gist: https://gist.github.com/SquidLord/4755840

-- Put in turtle startup file with: 
--    os.loadAPI("squid/turtleLib")

-- The MIT License (MIT)

-- Copyright (c) 2012 Alexander Williams

-- Permission is hereby granted, free of charge, to any person obtaining a copy
-- of this software and associated documentation files (the "Software"), to deal
-- in the Software without restriction, including without limitation the rights
-- to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-- copies of the Software, and to permit persons to whom the Software is
-- furnished to do so, subject to the following conditions:

-- The above copyright notice and this permission notice shall be included in all
-- copies or substantial portions of the Software.

-- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-- IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-- FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-- AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-- LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-- OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
-- SOFTWARE.

-- goodStr
--    String containing list of all good characters for directions
goodStr = "fblrudLR"


-- makeMoveTable(Lib) => Table
--    takes a Lib (egps, turtle) and builds a map of String->move function associations
function makeMoveTable(Lib)
  MT = {}
  
  MT.f = Lib.forward
  MT.b = Lib.back
  MT.l = Lib.turnLeft
  MT.r = Lib.turnRight
  MT.u = Lib.up
  MT.d = Lib.down
  MT.L = function() 
            Lib.turnLeft()
            Lib.forward()
            Lib.turnRight()
          end
  MT.R = function()
            Lib.turnRight()
            Lib.forward()
            Lib.turnLeft()  
          end
  return MT
end


-- StrToDirection(Cha, MoveTable) => Func
--    Takes a single-character string and returns the turtle
--    movement function associated with that direction
function chaToDirection(Cha, MoveTable)
  if not (string.find(goodStr, Cha)) then
    return false
  else
    return MoveTable[Cha]
  end
end


-- stringToMoves(String, Table, [Table]): => Table
--    Takes a string, a generated MoveTable, and an optional table in progress
--    Returns an ordered list of function calls
function stringToMoves(Str, MoveTable, OutTable)
  if (OutTable == nil) then -- If this is the first call of the func, init OutTable
    OutTable = {}
  end
  
  if (Str == "") then -- If there are no more cha's to process, return
    return OutTable
  else
    table.insert(OutTable, MoveTable[string.sub(Str, 1, 1)])
    return stringToMoves(string.sub(Str, 2),
                          MoveTable,
                          OutTable)
  end                                  
end

-- executeMoveTable(Table) => Bool
--    Executes a series of turtle moves as given in an ordered Table
function executeMoves(MoveTable)
  for _,Move in ipairs(MoveTable) do
    Move()
  end
end