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".



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 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.
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