Dan Ingalls wrote:

> One of the reasons we didn't actually act on these suggestions on the last
> go-round was that we got distracted by extending Squeak's numeric coercions to
> handle collections enabling APL-like examples as
> 
> #(1 2 3 4 5) * 2
> and 
> 2 * #(1 2 3 4 5).

This seems the appropriate context to consider set operations on
collections, such as union and difference:

#(1 2 3 4 5) asSet union: #(5 6) asSet  ==>> Set (1 2 3 4 5 6)

#(1 2 3 4 5) asSet intersect: #(5 6) asSet  ==>> Set (5)

This would handle removing and detecting duplicates and such, which seems to
crop up from time to time.

As a matter of fact, I would interpret + etc. on sets as set algebraic
operators:

set1 + set2   equivalent to   set1 union: set2

but this might certainly obfuscate.

The semantics of the operation would depend on the class of the receiver
(unlike sets, arrays etc. would not remove duplicates on union:).

To me, this seems another obvious candidate for having been previously
considered as well.

Also, is there a reason why there can't be a final period in a { } set
constructor? This seems inconsistent with periods in blocks and methods.
(Not too big a deal.)

ie. {1. 2.} bad; {1. 2} ok

Henrik