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Re: Any and Every... (was Re: Eval)

Hi there!

I think now the terminology gets completely out of hand. :-)

Let's say my language L has the simple types INTEGER and BOOLEAN as 
well as the compound types (well, type-constructors) ARRAY and 
RECORD. The "set of types in L" is {INTEGER, BOOLEAN, ARRAY, 
RECORD} where ARRAY and RECORD stand for "all declared ARRAY and 
RECORD types" (so there are lots).

The subset of simple types of L is {INTEGER, BOOLEAN} and the 
subset of compound types of L is {ARRAY, RECORD}. Now why would I 
*not* be able to talk about the intersection of these to subsets 
being empty? All elements are types, but they are *different* types.


On Tuesday, January 8, 2002, at 03:06 , KELLEHER,KEVIN (Non-HP-
Roseville,ex1) wrote:

> The phrases "the union of all types" and "the intersection
> of all types" do not make sense.  You have to have more
> than one group to have unions and intersections,
> but there is only one group: types.
Peter H. Froehlich []->[!]<-[] http://nil.ics.uci.edu/~phf/
OpenPGP: D465 CBDD D9D2 0D77 C5AF  353E C86C 2AD9 A6E2 309E