On 10/24/07, Gabriel Dos Reis wrote: > On Wed, 24 Oct 2007, Bill Page wrote: > | Gaby wrote: > | > so what wouold > | > > | > for i in PositiveInteger repeat > | > > | > does concretely? > | > > | > | '1..' is another (better?) name for PositiveInteger > > No, it is not. Both behave quite differently in many situations. >
Actually I agree with you. But what I should have said is that the domain PositiveInteger can subsume the operations of '1..'. > | So under my proposal 'for i in PositiveInteger repeat' should function > | identically to the way > | > | for i in 1.. repeat > > so you want to treat a domain as being identical to its ordered list > of values. But, a domain is not (just) its set of values. Of course you are right. I do *not* want to treat a domain as being identical to it's ordered list of values. A domain is many other things besides that. However I see no reason why most domains (at least those in the categories Finite and StepThrough) should not provide a standard mechanism for doing such iterations. > About about > > for i in List(Integer) repeat > > or > > for n in BinaryTree(Integer) repeat > Yes, List and BinaryTree should be able to provide such iterators. Sometimes (in particular in these cases) it is difficult to define a "standard" ordering but the particular default ordering that is chosen in each case can be easily documented and the alternatives produced by some auxillary operation or coercion. > | works now in the interpreter where '1..' denotes an object of > | 'UniversalSegment PositiveInteger'. > > But UniversalSegment is a *particular traversal view* of PositiveInteger. > Yes, I agree. Why not make in it the "standard" one for PositiveInteger? Regards, Bill Page. _______________________________________________ Axiom-math mailing list [email protected] http://lists.nongnu.org/mailman/listinfo/axiom-math
