Lua function call with parameter list in a string

they can't be sent as a list (It's in CoronaSDK, so I can't really modify the source, and have to adapt to it)

Sure it can. Watch:

function CallWithParametersInAList(FunctionToCall, paramsInList)
  return FunctionToCall(unpack(paramsInList))
end

See? Every array element in paramsInList will be unpacked into arguments to FunctionToCall. Also, every return value from FunctionToCall will be returned.

see

function test(a)
    print("this is lua test function."..a);
end

CallWithParametersInAList(test,{33333});

OUTPUT

this is lua test function.33333

You can call a lua function with as many parameters as you want. If the function expects more parameters, they will be set to nil. If the function expects too few parameters, the extra parameters sent will get ignored.

For example:

function f(a, b, c)
  print(a, b, c)
end

f(1, 2) -- prints: 1 2 nil

f(1, 2, 3) -- prints: 1 2 3

f(1, 2, 3, 4, 5) -- prints: 1 2 3

edit:

If you must get the parameters from a string and those parameters include things like tables and functions, you have little option but to get the string parsed by loadstring function:

-- s contains the parameters
s = '1,2,{1,2,3}'

-- f is the function you want to call
loadstring('f(' .. s .. ')')()  -- prints: 1  2  table: 0061D2E8

I'm not sure about CoronaSDK, but the loadstring function tends to be a bit slow. Try to avoid it if possible.

One of the best methods, in my opinion(and the one I use) is something like this:

function Call( ... )
    -- All passed arguments are stored in a default table named arg
    table.foreach( arg, print )
end

And, here's a working example on codepad - oDmVZ209.

I'd second Nicol Bolas that you are probably trying to solve the wrong problem, but if you still want to parse the string and turn it into a list of parameters, here is one way to do this (loadstring is not available in Corona environment; obviously this doesn't handle any type of hierarchical data):

function str2list(s)
  local parms = {}
  for p in s:gmatch("([^,]+),?") do table.insert(parms, p) end
  return unpack(parms)
end
print(str2list("param1, param2, param3, param4"))