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Re: BlueJ don't know what i did wrong

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On 28/02/13 02:40, Arved Sandstrom wrote:
> On 02/27/2013 08:24 AM, lipska the kat wrote:
>> On 27/02/13 10:45, Arved Sandstrom wrote:
>>> On 02/26/2013 07:30 AM, lipska the kat wrote:
>>>> On 26/02/13 09:59, Arved Sandstrom wrote:
>>>>> On 02/26/2013 05:23 AM, lipska the kat wrote:

[snip]

> I'm happy with the definition that for example Knuth or Sedgwick use
> (and about a million other people), where a deque is called a
> generalization of a queue or a stack. The reason a deque is called a
> generalization of a queue or a stack is because it is in fact more
> general than a queue or a stack, and combines features of both.
>
> Since a whole raft of CS authorities and other programming commentators
> are happy to call the deque a generalization of a queue or stack when
> writing about data structures, I'm pretty happy to accept this as a
> definition.

Yep, I agree, my stubborn determination to prove you wrong about this 
issue clouded my judgment. On this I concede. I am human, I am 
imperfect, I make mistakes.

However

I simply cannot agree with your assertion that

"a deque is not a queue, but a queue is a deque."

Enter the following into your favorite IDE

java.util.Queue queue = null;
java.util.Deque deque = null;
		
queue = deque;
//This compiles: Because we can store a reference to a Deque into a 
//reference to a Queue, a Deque *is a* Queue

deque = queue;
//This does not compile: Because we can't store a reference
//to a Queue into a reference to a Deque, a Queue *is not* a Deque

If a Queue were a Deque then we could call Deque methods on a Queue
Can we call Deque methods on a Queue? well I can't, can you?

I'd be interested to hear your thoughts on this.

lipska




-- 
Lipska the Kat©: Troll hunter, sandbox destroyer
and farscape dreamer of Aeryn Sun

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BlueJ don't know what i did wrong BlueJguywithoutskill <marvin.radke@htp-tel.de> - 2013-02-22 06:03 -0800
  Re: BlueJ don't know what i did wrong Joerg Meier <joergmmeier@arcor.de> - 2013-02-22 15:55 +0100
  Re: BlueJ don't know what i did wrong marvin.radke@htp-tel.de - 2013-02-22 07:13 -0800
    Re: BlueJ don't know what i did wrong Joerg Meier <joergmmeier@arcor.de> - 2013-02-22 16:24 +0100
      Re: BlueJ don't know what i did wrong marvin.radke@htp-tel.de - 2013-02-22 07:31 -0800
      Re: BlueJ don't know what i did wrong Eric Sosman <esosman@comcast-dot-net.invalid> - 2013-02-22 10:50 -0500
  Re: BlueJ don't know what i did wrong markspace <markspace@nospam.nospam> - 2013-02-22 10:43 -0800
  Re: BlueJ don't know what i did wrong marvin.radke@htp-tel.de - 2013-02-24 02:27 -0800
    Re: BlueJ don't know what i did wrong Joerg Meier <joergmmeier@arcor.de> - 2013-02-24 14:54 +0100
      Re: BlueJ don't know what i did wrong marvin.radke@htp-tel.de - 2013-02-24 06:15 -0800
    Re: BlueJ don't know what i did wrong lipska the kat <"nospam at neversurrender dot co dot uk"> - 2013-02-24 15:04 +0000
    Re: BlueJ don't know what i did wrong lipska the kat <"nospam at neversurrender dot co dot uk"> - 2013-02-24 16:29 +0000
      Re: BlueJ don't know what i did wrong Joerg Meier <joergmmeier@arcor.de> - 2013-02-24 18:21 +0100
        Re: BlueJ don't know what i did wrong lipska the kat <"nospam at neversurrender dot co dot uk"> - 2013-02-24 17:43 +0000
          Re: BlueJ don't know what i did wrong Joerg Meier <joergmmeier@arcor.de> - 2013-02-24 20:04 +0100
            Re: BlueJ don't know what i did wrong lipska the kat <"nospam at neversurrender dot co dot uk"> - 2013-02-24 19:24 +0000
              Re: BlueJ don't know what i did wrong marvin.radke@htp-tel.de - 2013-02-25 01:52 -0800
                Re: BlueJ don't know what i did wrong lipska the kat <"nospam at neversurrender dot co dot uk"> - 2013-02-25 11:10 +0000
                Re: BlueJ don't know what i did wrong "John B. Matthews" <nospam@nospam.invalid> - 2013-02-25 07:50 -0500
                Re: BlueJ don't know what i did wrong lipska the kat <"nospam at neversurrender dot co dot uk"> - 2013-02-25 13:35 +0000
                Re: BlueJ don't know what i did wrong "John B. Matthews" <nospam@nospam.invalid> - 2013-02-25 13:52 -0500
                Re: BlueJ don't know what i did wrong lipska the kat <"nospam at neversurrender dot co dot uk"> - 2013-02-25 19:54 +0000
                Re: BlueJ don't know what i did wrong Lew <lewbloch@gmail.com> - 2013-02-25 14:26 -0800
                Re: BlueJ don't know what i did wrong lipska the kat <"nospam at neversurrender dot co dot uk"> - 2013-02-26 09:08 +0000
                Re: BlueJ don't know what i did wrong Arne Vajhøj <arne@vajhoej.dk> - 2013-02-25 22:05 -0500
                Re: BlueJ don't know what i did wrong Arne Vajhøj <arne@vajhoej.dk> - 2013-02-25 22:08 -0500
                Re: BlueJ don't know what i did wrong lipska the kat <"nospam at neversurrender dot co dot uk"> - 2013-02-26 09:23 +0000
                Re: BlueJ don't know what i did wrong Arved Sandstrom <asandstrom2@eastlink.ca> - 2013-02-26 05:59 -0400
                Re: BlueJ don't know what i did wrong lipska the kat <"nospam at neversurrender dot co dot uk"> - 2013-02-26 11:30 +0000
                Re: BlueJ don't know what i did wrong Arved Sandstrom <asandstrom2@eastlink.ca> - 2013-02-27 06:45 -0400
                Re: BlueJ don't know what i did wrong lipska the kat <"nospam at neversurrender dot co dot uk"> - 2013-02-27 11:58 +0000
                Re: BlueJ don't know what i did wrong lipska the kat <"nospam at neversurrender dot co dot uk"> - 2013-02-27 12:24 +0000
                Re: BlueJ don't know what i did wrong Arved Sandstrom <asandstrom2@eastlink.ca> - 2013-02-27 22:40 -0400
                Re: BlueJ don't know what i did wrong lipska the kat <"nospam at neversurrender dot co dot uk"> - 2013-02-28 08:53 +0000
                Re: BlueJ don't know what i did wrong Arved Sandstrom <asandstrom2@eastlink.ca> - 2013-02-28 17:14 -0400
                Re: BlueJ don't know what i did wrong lipska the kat <"nospam at neversurrender dot co dot uk"> - 2013-03-01 08:45 +0000
                Re: BlueJ don't know what i did wrong markspace <markspace@nospam.nospam> - 2013-02-26 08:33 -0800
                Re: BlueJ don't know what i did wrong Arne Vajhøj <arne@vajhoej.dk> - 2013-02-25 22:19 -0500
                Re: BlueJ don't know what i did wrong Arne Vajhøj <arne@vajhoej.dk> - 2013-02-25 22:02 -0500
                Re: BlueJ don't know what i did wrong marvin.radke@htp-tel.de - 2013-02-25 09:54 -0800
                Re: BlueJ don't know what i did wrong lipska the kat <"nospam at neversurrender dot co dot uk"> - 2013-02-25 18:25 +0000
                Re: BlueJ don't know what i did wrong Joerg Meier <joergmmeier@arcor.de> - 2013-02-26 16:13 +0100
                Re: BlueJ don't know what i did wrong lipska the kat <"nospam at neversurrender dot co dot uk"> - 2013-02-26 16:40 +0000
                Re: BlueJ don't know what i did wrong Joerg Meier <joergmmeier@arcor.de> - 2013-02-26 18:19 +0100
                Re: BlueJ don't know what i did wrong markspace <markspace@nospam.nospam> - 2013-02-25 08:34 -0800
    Re: BlueJ don't know what i did wrong Lew <lewbloch@gmail.com> - 2013-02-24 12:38 -0800

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