[squeak-dev] PositionableStream >> peekBack

Chris Cunningham cunningham.cb at gmail.com
Fri Jun 30 00:34:02 UTC 2017

What gives you a view of what would be returned if you sent #back is:
PositionableString (and subclasses): #last
StandardFileStream (and subclasses): #peekLast
* this last one is matches to #back as defined in MutliByteFileStream.
 #last could be used, but since it uses the internal collection instVar, it
may give odd results. I don't know - haven't tried it.


On Wed, Jun 21, 2017 at 6:00 AM, Jakob Reschke <jakob.reschke at student.hpi.de
> wrote:

> Hi all,
> I just stumbled upon the behavior of #peekBack. I expected that it
> would give me a "preview" of what I would get when I send #back, but
> without changing the position of the Stream (like #peek does for
> #next). Or in other words, I expected to get the last read (or
> written) element.
> As it turned out it answers the next-to-last element instead. There
> even is a test case in RWBinaryOrTextStreamTest for this behavior.
> But does it make sense? I have my doubts mainly because of the
> inconsistency with the return value of #back.
> There is also #peekLast, which does what I expected, but it is only
> defined for File- and WriteStream and the comment says it is intended
> to get the last put element, not a last read/extracted/next-ed
> element.
> Kind regards,
> Jakob
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.squeakfoundation.org/pipermail/squeak-dev/attachments/20170629/df436151/attachment.html>

More information about the Squeak-dev mailing list