referencing table elements within the same table constructor

["Warlich, Christof" <christof.warlich@...>]

Hi,

 

being pretty new to Lua, I’m heavily using it as a configuration language for my C++ code. To make the configuration as user friendly as possible, I selected a table-driven approach for the configuration file, as it offers an easy-to-read hierarchy, e.g.:

 

function setFunction()

    print("received SET command")

end

function statusFunction()

    print("received STATUS command")

end

interface = {

    port = "/dev/ttyS0",

    baud = 9600,

    incoming = {

        SET = setFunction,

        STATUS = statusFunction

    }

}

 

So far, this works just great, even allowing global Lua-Functions to be referenced from within the table.

 

My next idea was to put the functions’ code directly into the table, making the configuration file even more readable:

 

interface = {

    port = "/dev/ttyS0",

    baud = 9600,

    incoming = {

        SET = function()

                  print("received SET command")

              end,

        STATUS = function()

                     print("received SET command")

                 end

 

    }

}

 

But while this simple example still works fine, it seems that there is no way reference another table value from the same table constructor: To give an example, I cannot print the port from my functions:

 

interface = {

    port = "/dev/ttyS0",

    baud = 9600,

    incoming = {

        SET = function()

                  print("received SET command from:")

                  print(interface["port"]) -- error!!

              end,

        STATUS = function()

                     print("received SET command")

                 end

 

    }

}

 

Is there a way to work around this problem, ideally by keeping everything within the same table constructor?

 

Thanks for any suggestions,

 

Christof