Ok, last time - I hope. :-)

If I'm right the reason why the error came up at the first empty directory  
and if there has been none, then only the first subtree is traversed,  
because of the recursive rebinding of the word 'aFile to the repeat block.  
While recursing down the first branch of the directory tree the block gets  
all the time bound to a new version of 'aFile. Upon returning back from  
the recursion the function one level up doesn't find any more the 'aFile  
 from before the recursive call and thus the test doesn't work or even  
fails. Fails when 'aFile has been bound to no value in the recursion when  
the directory was empty or to the last value of the file in the deepest  
directory, which just gets added as often as during the walk up in the  
tree some files (no directories) are encountered, because always the  
second block of 'either gets executed.

:-)

Just a question to somebody who might know: One of the reasons why the  
binding mechanisms of Rebol are necessary is to make the keywordlessness  
possible, else something like 'repeat wouldn't be possible, right ???
But nevertheless I think these binding issues should be one of the first  
things to be explained to a newcomer. It is an important property of Rebol  
and should be treated like this. If there are chances to encounter these  
things in normal life they have to be explained appropriately already on  
the beginning and not on some articles (Ladislavs Bindology) or some  
sidenote in the documentation that a function changes it's body argument.  
Without deeper glue of Rebol it's hardly to get the reason and just simply  
using hints like using copy/deep on a block in some circumstances is hard  
to remember and hard to explain. Thus if Rebol is like this it should be  
put on the frontplate. ????!!!!

Michael

On Sun, 10 Apr 2005 23:43:04 +0300, Michael Berg <[EMAIL PROTECTED]> wrote:

>
> :-) Sorry, I maybe posted it too fast. I'm still searching for the the  
> why.
>
> I think that's one of the bad parts of Rebol. This dynamic binding might
> be powerful, but it causes a lot of trouble as well. For instance besides
> your note, I don't get right now why it for instance without copy/deep
> brings up an error when it encounters an empty directory, und with
> copy/deep it runs. (at least without the error message)
>
> Nevertheless it works with copy deep if you add in the argument section a
> "/local rez". I think you forgot to make rez local to the function as it
> is by standard global and gets everytime deleted. :-)
>
> Michael
>
> On Sun, 10 Apr 2005 23:13:14 +0300, <[EMAIL PROTECTED]> wrote:
>
>>
>> Thanks!
>> I noted this (copy/deep), but now it is working without errors,
>> but not corectly:
>> First line is wrong - first directory of base dir is added,
>> and then just files of base dir.
>>
>> brgds
>> Janeks
>>
>> On 10 Apr 2005 at 22:44, Michael Berg wrote:
>>
>>>
>>> Hi,
>>>
>>> if you change the repeat line to
>>>
>>> repeat aFile read thisDir copy/deep [
>>>
>>> it will work, as repeat modifies the block to be repeated. See also at
>>> http://www.rebol.com/docs/words/wrepeat.html the user comment from
>>> Ladislav.
>>>
>>> Didn't know this myself - until now. :-)
>>>
>>> Michael
>>>
>>>
>>>
>>> On Sun, 10 Apr 2005 21:36:25 +0300, <[EMAIL PROTECTED]> wrote:
>>>
>>> >
>>> > Hi, Rebolers!
>>> >
>>> > I am new in rebol scopes. So it seems, that it cause problems in my
>>> > recursive directory reading function. Could somebody  give me a bit
>>> > more description about variable scopes in following case:
>>> >
>>> > readChaptDir2: func [ thisDir ] [
>>> >   rez: copy thisDir
>>> >   repeat aFile read thisDir [
>>> >           either #"/" = last aFile [
>>> >                   repend rez [ "<br>dir:" join thisDir aFile ]
>>> >                   repend rez readChaptDir2 join thisDir aFile
>>> >           ][
>>> >                   repend rez [ <br> aFile ]
>>> >           ]
>>> >           
>>> >   ]
>>> >   return rez
>>> > ]
>>> >
>>> > Looking forward,
>>> >
>>> > Janeks
>>> >
>>>
>>>
>>> --
>>> To unsubscribe from the list, just send an email to
>>> lists at rebol.com with unsubscribe as the subject.
>>>
>>>
>>
>>
>>
>
>


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