OpenEuphoria

2. Re: Re[4]: Return from nested subroutines (still goto discussion)

• Posted by Tone Škoda <tskoda at email.si> Nov 13, 2004
• 472 views

here is one trick i just thought of, but i think it's not too good coding style:

btw i don't think "if then" takes so much time.

integer G

procedure r ()
	...
	if r(x+1, i) then
		G = 3
        	return
	end if
	...
end procedure

procedure main (0
G = 1
while 1 do
	if G >= 3 then
		exit
	end if
	r ()	
	G += 1
end while
end procedure ()

"while" isn't slower than "if", is it?


unknown wrote:
> 
> Ya,  this  is  what  I mean by decreasing performance. Having to check
> return  value  for  each  iteration  (even when the return value is 0)
> would consume maybe about 10% of the time.
> 
> How  about  using  threads?  I  never  program  in  threads, but is it
> possible  to  run  r()  in  seperate  thread  then  kill  the  thread
> immediately when the "success" is printed.
> 
> Kat wrote:
> G> Jumping into/out of proceedures has never been on my wish list, quite the
> G> contrary.
> 
> GOTO  never  been  necessary for me except for exiting the stack :P
> -- without decreasing performance
> 
> 
> G> Does this work? I got x = 5 and y = 3. The trick is to use functions
> G> and pass down a 'success' value, like here I use 1 for success, 0 for
> G> failure. Whenever there is a success (or 1) I exit the current loop
> G> and/or return. I've actually gotten used to this style of coding and I
> G> prefer it over goto. This just seems more logical that jumping around
> G> code all willy-nilly.
> 
> G> }}}
<eucode>
> G> sequence d
> G>     d = {0,0,0,0,0}
> 
> G> function sum( sequence x )
> G> -- calculate the sum of
> G> -- all values in x
> G> atom val
> G>     val = 0
> G>     for i = 1 to length(x) do
> G>         val += x[i]
> G>     end for
> G>     return val
> G> end function
> 
> G> function r(integer x, integer y)
> G>     d[x] = y
> G>     if x = 5 then
> G>         if sum(d) = 10 then
> G>             printf(1, "x = %d\ny = %d\n", {x,y})
> G>             puts(1, "success\n")
> G>             return 1
> G>         end if
> G>     else
> G>         for i = 0 to 3 do
> G>             if r(x+1, i) then
> G>                 return 1
> G>             end if
> G>         end for
> G>     end if
> 
> G>     return 0
> G> end function
> 
> G> procedure main()
> G>     for i = 0 to 3 do
> G>         if r(1, i) then
> G>             exit
> G>         end if
> G>     end for
> 
> G>     puts(1, "program end\n")
> G> end procedure
> 
> G> main()
> G> </eucode>
{{{

> 
>