Print Page - Optional Arguments Within a Function

Title: Optional Arguments Within a Function
Post by: CW on 2013-Mar-20

Hey all, I need someone to help jog my memory.

I seem to remember reading somewhere that it is possible to declare optional arguments which can be passed to a function, but which can be omitted; in which case the function uses the default value. I can't find that text again, now that I need the ability. (Was it in GLbasic?)

It would look something like: (Just a quick and dirty example..)

FUNCTION Example: x%,y%, [color% = 0] //where color% can either be passed, or not, by the calling program.
SETPIXEL x,y,color
ENDFUNCTION

If memory serves, optional arguments are allowed provided they are placed at the end of the declaration.
I COULD create two or more variations on the same function, or create nesting wrappers around the functions, but why create two when one will do?

Can someone give me a hand? :)

-CW

Title: Re: Optional Arguments Within a Function
Post by: MrTAToad on 2013-Mar-20

You do something like

Code (glbasic) Select

FUNCTION a%:t%=1,t2%=5
ENDFUNCTION

You can then do :

Code (glbasic) Select

g=a()
g=a(1)
g=a(2,3)

Title: Re: Optional Arguments Within a Function
Post by: CW on 2013-Mar-20

Thanks Mr.Toad, that's just what I was looking for.
I was adding a lot of extra garbage which I didn't need.

Cheers! :happy:
-CW

GLBasic forum

Main forum => GLBasic - en => Topic started by: CW on 2013-Mar-20