Implictely is more error prone.

On Wed, Dec 19, 2001 at 04:12:02PM -0800, Lars Torben Wilson wrote : 
> Markus Fischer writes:
> >     Why not just check the type of the parameter? No conversion
> >     needed at all. If its a long -> exit/no show it. If anything
> >     else (well, thats to argue, but not the point) exit and show.
> >     It would be that easy. And, in that case, I don't care about
> >     the number of broken scripts. Prove there are more then you
> >     got fingers on your hand. And even those, you can fix under a
> >     second.
> 
> Because then exit('5') and exit(5) would still have different
> behaviours, which is the current situation and which is the root of
> the problem. If the implicit conversions are done, we end up with:
> 
> exit('5')           : prints '5' and sets exit code to 5
> exit(5)             : prints '5' and sets exit code to 5
> exit('Some message'): prints 'Some message' and sets exit code to 0
> 
> ...etc. Existing scripts which use exit() to output a message would
> still output the same message they currently do, so we maintain
> backward compatibility. The only difference would be that exit() would
> work the same way other php functions do--for instance, we expect the
> same output from 'echo chr(65);' and 'echo chr("65");', right? Why
> should exit be any different?
> 
> > On Wed, Dec 19, 2001 at 03:33:15PM -0800, Lars Torben Wilson wrote : 
> > > Vlad Krupin writes:
> > > > Please, understand me correctly - I have nothing against exit() working 
> > > > in the same manner regardless of the type of the argument. I would love 
> > > > to see that. The problem is that (1) it already accepts a string, and 
> > > > has been working that way for a long time, so this can't go away, and 
> > > > (2) there is no other way (AFAIK) to set exit codes, and some people 
> > > > need that. Those are somewhat contradicting requirements, so we might 
> > > > have to compromise.
> > > > 
> > > > I do have a problem with the compromise you proposed though, if I 
> > > > understood you correctly. You suggest using something like
> > > > 
> > > > > exit("1boo")
> > > >
> > > > And having exit() parse the first digit out. That's BAD. What if
> > > 
> > > It's not parsing anything. It's just converting to int using the well
> > > documented rules of string to integer conversion which have existed in
> > > the language for years. The language is pretty much impossible to use
> > > without running into implicit type conversions--it's designed for
> > > it. That's why the current behaviour of exit() breaks consistency.
> > > Please, check out the Type Juggling section of the manual. This
> > > shouldq not a special case, but it currently is treated as one. It
> > > should behave the way the rest of the language behaves. 
> > > 
> > > > someone already uses exit("123, 456 servers are unavailable"); or
> > > > something similar. How should we parse something like that? Chances
> > > 
> > > Again, we don't. We let the language deal with it like it does every
> > > other string->integer conversion.
> > > 
> > > > of that are slim, but just as good as Zeev's argument where he says
> > > > that there are scripts out there that rely on the current
> > > > implementation of exit(), e.g. one of his own. Jamming two values
> > > > into a storage space designed for a single value (a string) is bad
> > > > :(
> > > 
> > > In the case you gave, the only difference the user would notice
> > > would be that the exit status of the script would be 123 instead of
> > > 0. It would still print out the '123, 456 servers are unavailable'.
> > > 
> > > > Vlad
> > > > 
> > > > 
> > > > 
> > > > Lars Torben Wilson wrote:
> > > > 
> > > > >Vlad Krupin writes:
> > > > >
> > > > >>Lars Torben Wilson wrote:
> > > > >>
> > > > >>>Perhaps I have not explained my position. I don't care whether it
> > > > >>>outputs the exit status as a string--as long as it sets the error code
> > > > >>>appropriately *as well*. By appropriately, I mean that 'exit("boo");'
> > > > >>>would a) print 'boo' and b) return with exit status 0, but
> > > > >>>'exit("1boo")'; would a) print '1boo' and b) return with exit status
> > > > >>>1. This would be consistent with PHP's type conversion rules, and
> > > > >>>would also tend to behave in the way that the programmer expects it
> > > > >>>to.
> > > > >>>
> > > > >>Yikes. This is way worse than overloading. In school they called that 
> > > > >>data-coupling, I think. In real life this is called a hack.
> > > > >>
> > > > >>Sorry, but a -1 on this.
> > > > >>
> > > > >>Vlad
> > > > >>
> > > > >
> > > > >No, it's called loose typing. See
> > > > >
> > > > 
>>http://www.php.net/manual/en/language.types.string.php#language.types.string.conversion
> > > > >
> > > > >We have a language here which considers the integer value of "5" to
> > > > >be 5, and an exit() construct which ignores that.
> > > > >
> > > > >For instance:
> > > > >
> > > > >  shanna% php -q
> > > > >  <?php exit('5'); ?>
> > > > >  5
> > > > >
> > > > >  shanna% echo $?
> > > > >  0
> > > > > 
> > > > >  shanna% php -q
> > > > >  <?php exit(5); ?>
> > > > >  5
> > > > >
> > > > >  shanna% echo $?
> > > > >  5
> > > > >
> > > > >How much sense does this make? None, as far as I can see.
> > > > >
> > > > >What I'm proposing is to make the behaviour of exit() _not_ depend on
> > > > >the type of its argument. At present if the argument is an integer
> > > > >exit() prints it and sets the error status, but if it's any other
> > > > >type, exit() just prints it and doesn't set the exit status. This is
> > > > >more complex than my proposal: no matter what the argument is, print
> > > > >out its string value, and set the exit status to its integer value.
> > > > >
> > > > >AFAICT exit() is currently broken wrt how it handles the type of its
> > > > >argument. 
> > > > >
> > > > >
> > > > 
> > > > 
> > > > 
> > > 
> > > -- 
> > >  Torben Wilson <[EMAIL PROTECTED]>
> > >  http://www.thebuttlesschaps.com
> > >  http://www.hybrid17.com
> > >  http://www.inflatableeye.com
> > >  +1.604.709.0506
> > > 
> > > 
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> 
> -- 
>  Torben Wilson <[EMAIL PROTECTED]>
>  http://www.thebuttlesschaps.com
>  http://www.hybrid17.com
>  http://www.inflatableeye.com
>  +1.604.709.0506

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