on1 construct

[Bruce Karsh]

> One contruct that I've always wanted to have is:
> 
> function ()
> {
>     on1  {
> 	bla, bla, bla...
>     };
> 
>     etc...
> }

  It's a little cryptic, but here is one way to do it:

-- on1.c ------------- Cut Here -----------------------------------------

   #define on1() static int notfirst= -1; if(!(++notfirst ? notfirst=1 : 0))
   main()
   {
   sub();
   sub();
   sub();
   }
   
   sub()
   {
   on1()
     printf("first time\n");
   else
     printf("not first time\n");
   }
---------------------- Cut Here -----------------------------------------
-- 
Bruce Karsh                                        ---------------------------
Univ. Wisconsin Dept. of Geology and Geophysics    |                         |
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