LUA COMMANDS

LUA INIT
    *no parameters*
Starts the lua system. Must be called before other commands.

LUA DEINIT
    *no parameters*
Frees the lua system.

LUA COMPILE FILE
    inputfile,outputfile
This function will perform required preprocessing on inputfile, and write the result to output file. This outputted file can then be called by the LUA EXECUTE FILE command. This function is only needed if a script is going to be executed frequently, as the preprocessing could add a performance hit if done very frequently.

LUA EXECUTE FILE
    filename,UsePreprocess
Executes the lua code contained in the given file.
If UsePreprocess is set to true, then the DLL will perform the needed processing on the lua script at this time. Set this to false if the preprocessing has already been done by the LUA COMPILE FILE command.

LUA EXECUTE STRING
    code_as_string
Executes the lua code contained in the given string.

LUA CREATE TABLE
    table_name
This function creates a new lua table with the given name. You can also create tables inside of tables.
Some samples:
"testtable"
"testtable[1]"
"testtable.one"
"testtable.one[10]"

LUA GET INT
    (variable_name)
    returns integer
Gets the value of an integer lua variable with the given name. You can get values from a table using this function.
Some samples:
"myvar"
"myvar[1]"
"myvar.one[2]"

LUA GET FLOAT
    (variable_name)
    returns float
Gets the value of a float lua variable with the given name. You can get values from a table using this function.

LUA GET STRING
    (variable_name)
Gets the value of an string lua variable with the given name. You can get values from a table using this function.

LUA SET INT
    variable_name,integer_value
Sets the value of an integer lua variable with the given name. You can set values for a table using this function
Some samples:
"myvar",10
"myvar[1]",10
"myvar.one[2]",1

LUA SET FLOAT
    variable_name,float_value
Sets the value of a float lua variable with the given name.

LUA SET STRING
    variable_name,string_value
Sets the value of an string lua variable with the given name.

LUA POP INT
    (*no parameters*)
    returns integer
Pops an integer off the top lua stack. If the value on top of the stack is not an integer, an error occurs.

LUA POP FLOAT
    (*no parameters*)
    returns float
Pops a float off the top lua stack. If the value on top of the stack is not a float, an error occurs.

LUA POP STRING
    (*no parameters*)
    returns string
Pops a string off the top lua stack. If the value on top of the stack is not a string, an error occurs.

LUA TOP IS INT
    (*no parameters*)
    returns bool
Returns true if the value on top of the stack is an integer. Otherwise false is returned.

LUA TOP IS FLOAT
    (*no parameters*)
    returns bool
Returns true if the value on top of the stack is a float. Otherwise false is returned.

LUA TOP IS STRING
    (*no parameters*)
    returns bool
Returns true if the value on top of the stack is a string. Otherwise false is returned.

LUA PUSH INT
    integer_value
Pushes an integer onto the lua stack.

LUA PUSH FLOAT
    float_value
Pushes a float onto the lua stack.

LUA PUSH STRING
    string_value
Pushes a string onto the lua stack.

LUA PUSH FUNCTION
    function_name
Pushes a lua function onto the stack to be called shortly. After you have pushed a lua function onto the stack, you must push the arguments onto the stack using the "lua push" functions. Then you use the "LUA CALL FUNCTION" function.

LUA CALL FUNCTION
    number_of_arguments,number_of_return_values
Calls the lua function that was previously pushed onto the stack. You must put the number of arguments that you pushed onto the stack. You must also tell how many return values there will be. The return values will be pushed onto the stack where you can retrieve them using the "lua get" functions.

LUA REGISTER FUNCTION
    function_name,pointer_to_function
Registers a dbpro user defined function with lua. You can set the function name to whatever you want, so long as it doesn't start with a number or include spaces. To get the function pointer, use IanM's Matrix1Util_20.dll plugin. The DBPro function must return how many return values have been pushed onto the stack.

Notes: You cannot compile a script using luac.exe that utilizes user dbpro functions. If you absolutely must compile the script, you must not call the functions using their name. Instead call them using returnval=DBPro("add",arg1,arg2)

Here is some example code:

`This is the dbpro function you want to call from inside a script
function add()
    a as integer
    b as integer
    c as integer
    `The parameters of the function are pushed onto the stack
    `Retrieve them by popping them off the stack
    a=lua pop int()
    b=lua pop int()
    c=a+b
    `print the result in dbpro
    print c
    `return values are pushed back onto the stack
    `you can return more then one value if you want to.
    lua push int c
`return how many return values there are
endfunction 1

`this is the dbpro function that registers the add() function with lua
`you would call this funciton before you execute the lua script that
`accesses the "add()" function
function add_register()
    `the "get ptr to prev function()" is in the Matrix1Util_20.dll plugin
    `the command I'm using here returns the pointer to the function that is
    `currently above this one, which is the "add()" function
    lua register function "add",get ptr to prev function()
endfunction

`This is the lua script file
result=add(1,2)

LUA GET ARG COUNT
    (*no parameters*)
    returns integer value
This returns how many arguments are being passed to a user dbpro function from inside a lua script. This function is useful when you want to call a dbpro  user function with a variable number of arguments from a lua script.

LUA ERROR OCCURED
    (*no parameters*)
    returns boolean value
This function returns true if an error has occured in the lua system. Otherwise false is returned.

LUA ERROR MSG$
    (*no parameters*)
    returns string value
Returns the latest error message generated by the lua system.

LUA ERROR RESET
    (*no parameters*)
Clears all error messages in the lua system.

LUA REGISTER ERROR FUNCTION
    pointer_to_function
Allows you to register a user dbpro function that will be called when an error occures in the lua system. Your user defined function must take one string argument, which is the error message. You can then do what you like to handle the error. This saves the hassle of using "LUA ERROR OCCURED" after every lua function call to check for errors.

Example:

function Error(str as string)
    exit prompt "Lua Error!",str
    end
endfunction

function Error_register()
    lua register error function get ptr to prev function()
endfunction


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