Dynamic Function Calls

[JC]

Hi Folks,

I not sure if what I am trying to do is possible, hopefully someone will be able to shed some light. I want to pass a function name to a second function and get the second function to call the first one.

eg:

Code: Select all

Main(SubMain,"blah")


function Main(pName,pstuff)

execute function (pName)

stuff........

end 


function SubMain()

stuff here........

end 

Can it be done ?

TIA,
JC

[romero126]

Yes

Code: Select all

Variables are handled as functions.
So any variable can be passed off as a function
If it doesnt error out that is.




function Main(pName, pStuff)
	if (type(pName) == "function") then
		result = pName() -- result is whatever pName returns
	else
		-- Not a function!@#?!
	end
	
	print(result)

end

function MySub()
	-- blah blah blah
	return "value" -- returns back to main.
end

For more information http://www.lua.org/manual/5.0/manual.html#2.5.8

[daurnimator]

why wouldn't you?

try: (code works)

Code: Select all

function SubMain()
        screen:print(0,0,"test",Color.new(255,0,0))
end
function Main(func)
        while true do
                screen:clear(Color.new(255,255,255))
                func()
                screen.flip()
        end
end

Main(SubMain)

[daurnimator]

damn, beat me ;)

[JC]

Wonderful. Thanks for the help (and the quick replies).

JC

[romero126]

why wouldn't you?

try: (code works)

Code: Select all

function SubMain()
        screen:print(0,0,"test",Color.new(255,0,0))
end
function Main(func)
        while true do
                screen:clear(Color.new(255,255,255))
                func()
                screen.flip()
        end
end

Main(SubMain)

No error-checking.
No way to terminate loop.
screen:clear() doesnt need to be called.
screen.flip() -- might not be needed.
Too much extra code and not enough explination.
Sorry I dont mean to nitpick at your code, but I thought it might help!