Hi Timothy,

On Sat, Oct 24, 2020 at 3:32 AM gettimothy via Squeak-dev <
squeak-dev at lists.squeakfoundation.org> wrote:

> Hi Folks,
>
> Pardon the noobish "eyes of wonder" on the following.
>
> Recently, Eliot asked...
>
>    what is the value of
>       { (Float infinity basicAt: 1) hex.
>         (Float infinity basicAt: 2) hex.
>         (BoxedFloat64 infinity basicAt: 1) hex.
>         (BoxedFloat64 infinity basicAt: 2) hex.
>          BoxedFloat64 infinity == Float infinity }
>
> The result is:
>
>
> #('16r7FF00000' '16r0' '16r7FF00000' '16r0' true)
>
> This shows that the stuff in an Array is evaluated BEFORE the array is
> "produced".
>

These are called Array Tuples, and Dan Ingalls added them to Squeak many
years ago.  They are lovely concise forms, way more convenient than Array
with: with: with: ... and not limited in size.  Since Dan adding them
several dialects have followed suit.  Alas we've yet to see a new edition
of the Blue Book to mention these and other great improvements (e.g.
ByteArray literals, Vassili Bykov's ifNil:ifNotNil:, closures) although I
do dream of doing a revised blue book with a modern VM specification in the
last section.  And I'd love to see a Red Book on the Squeak tools.
Monticello is, for example, very beautiful, and should be more widely
praised, used, and documented.

>
> This is NOT in the Terse Guide and I do not recall seeing it in the books
> I read when I first started Squeak.
>

It should be :-)

>
> It is a very handy tool.
>
> I guess the behavior makes sense, as an Array is not a Block . Also,
> putting the same stuff in an OrderedCollection gives the same behavior.
>
>
> |x|
> x := OrderedCollection new.
> x add:(Float infinity basicAt: 1) hex.
> x add:(Float infinity basicAt: 2) hex.
> x add:(BoxedFloat64 infinity basicAt: 1) hex.
> x add:(BoxedFloat64 infinity basicAt: 2) hex.
> x add: BoxedFloat64 infinity == Float infinity .
> x inspect.
>
>
> The construct is very reminiscent of on of the early lessons in the SICP
> series,
>
>
> Anyhoo, one more cool thing to add to the toolbox.
>
> cheers.
>
>
>

-- 
_,,,^..^,,,_
best, Eliot
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