[Info-vax] DEC Basic and dynamic memory ?

[Dave Froble]

On 1/31/2022 8:48 AM, Simon Clubley wrote:
> On 2022-01-30, Dave Froble <davef at tsoft-inc.com> wrote:
>> On 1/30/2022 7:14 PM, Simon Clubley wrote:
>>> On 2022-01-30, Arne Vajhøj <arne at vajhoej.dk> wrote:
>>>> On 1/30/2022 7:03 PM, Simon Clubley wrote:
>>>>>                            There's also the required copying of the
>>>>> current data every time you grow the tree.
>>>>
>>>> That is common practice in many languages for dynamic
>>>> sized data structures needing linear backing.
>>>>
>>>
>>> But elsewhere you have the choice of whether to use something
>>> like a Vector or if you need to build a tree structure yourself.
>>>
>>> Specifying the growth increment of a linear structure is also
>>> a tradeoff but you are not forced to use a linear structure if
>>> you can build real trees and that's a better choice.
>>>
>>> Simon.
>>>
>>
>> Where do you come up with the idea that in Basic the nodes in a tree must be
>> linear?  They rarely are.  There usually are forward and backward pointers in a
>> linked list / tree.  Logically linear, but not physically linear.
>>
>
> Read again David. Arne and I am talking about the backing storage
> required by DEC Basic being linear.

Logically yes, physically no.

>> You're not appearing very knowledgeable Simon.
>>
>
> I've done this kind of thing quite a few times. There's a reason
> why I chose this example to see how it would be implemented in DEC Basic.
>
> So yes, I know exactly what I am talking about.
>
> Simon.
>


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