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Re: Program logic weirdness?

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In article <2f7c3181-f823-4cbf-9f86-c3d43e96f5cf@googlegroups.com>,
<jonas.thornvall@gmail.com> wrote:

> I think you are totally wrong Ben, we are basicly speaking about a
> print/write function, and if one should be able to steer what will be
> printout *before* one goes into the loop. 
> 
> Otherwise you will have to *fiddle* and doing unneccessary checks *within*
> loop.
> 
> If you can not see this, you may still be a good programmer but i am sure any
> program language you developed would be *convoluted*. 
> 
> This is not even logic, its mostly common sense and i find it a bit weird
> that some people whose profession is programming totally lose it.

I haven't been following this from the beginning, so I am not quite
sure what is being asked for here. ISTM that you are talking about
printing inside a loop, with perhaps a condition attached to the
printing. Something like:

for  (i=0;  i<limit;  i++)
     {
     if  (cond)  print ( ... );
     }

Now you are saying that cond is perhaps complicated and you don't want
to be recomputing that each time around the loop.

I see two possibilities:

1) cond does not depend on the loop counter, i.

2) cond *does* depend on the loop counter, i.


In case (1) you simply optimise it by taking the if out of the loop and
doing:

if  (cond)
     {
     for  (i=0;  i<limit;  i++)
          {
          print ( ... );
          }
     }

In case (2) you *cannot* do that and you *must* leave the if as it is.
This is true whether or not cond is simple or complicated.

If you do not understand why this is so, then I suggest you need to
learn how computer processors work.

Or are you asking a different question altogether? If so then you have
not expressed it clearly.

-- 
"The idea that Bill Gates has appeared like a knight in shining armour to
 lead all customers out of a mire of technological chaos neatly ignores 
 the fact that it was he who, by peddling second-rate technology, led them
 into it in the first place."                             - Douglas Adams

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Thread

Program logic weirdness? jonas.thornvall@gmail.com - 2014-04-25 22:53 -0700
  Re: Program logic weirdness? jonas.thornvall@gmail.com - 2014-04-25 22:57 -0700
    Re: Program logic weirdness? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-26 12:35 +0100
      Re: Program logic weirdness? jonas.thornvall@gmail.com - 2014-04-26 07:59 -0700
        Re: Program logic weirdness? jonas.thornvall@gmail.com - 2014-04-26 08:11 -0700
        Re: Program logic weirdness? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-26 22:34 +0100
          Re: Program logic weirdness? jonas.thornvall@gmail.com - 2014-04-27 00:44 -0700
            Re: Program logic weirdness? Tim Streater <timstreater@greenbee.net> - 2014-04-27 13:20 +0100
              Re: Program logic weirdness? jonas.thornvall@gmail.com - 2014-04-27 06:09 -0700
                Re: Program logic weirdness? Tim Streater <timstreater@greenbee.net> - 2014-04-27 18:30 +0100
                Re: Program logic weirdness? jonas.thornvall@gmail.com - 2014-04-27 12:13 -0700
                Re: Program logic weirdness? jonas.thornvall@gmail.com - 2014-04-28 02:33 -0700
              Re: Program logic weirdness? jonas.thornvall@gmail.com - 2014-04-27 06:25 -0700
              Re: Program logic weirdness? Denis McMahon <denismfmcmahon@gmail.com> - 2014-04-27 14:55 +0000
            Re: Program logic weirdness? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-27 15:41 +0100
              Re: Program logic weirdness? jonas.thornvall@gmail.com - 2014-04-27 13:57 -0700
  Re: Program logic weirdness? jonas.thornvall@gmail.com - 2014-04-25 23:18 -0700
  Re: Program logic weirdness? jonas.thornvall@gmail.com - 2014-04-25 23:23 -0700
  Re: Program logic weirdness? Christoph Michael Becker <cmbecker69@arcor.de> - 2014-04-26 15:06 +0200
    Re: Program logic weirdness? jonas.thornvall@gmail.com - 2014-04-26 08:00 -0700
    Re: Program logic weirdness? jonas.thornvall@gmail.com - 2014-04-26 08:06 -0700

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