Re: [Axiom-developer] semantics of #1

[Martin Rubey]

It's worse, the following works:

        interpolate(qx, lx, ly, m, k) ==
            px := RationalInterpolation(lx, ly, m, k)$RIA(F, UP(xx, F))

            (px case "failed") => "failed"

            if ((qnum := retractIfCan(numer qx)@Union(F, "failed")) case F) and
               ((qden := retractIfCan(denom qx)@Union(F, "failed")) case F) then
              q := qnum/qden
              una := px.unattainable
              if any?(q::F=elt(lx, #1), una) then return "failed"
--              for i in px.unattainable repeat
--                if elt(lx, i)=q then return "failed"

            [elt(px.function, qx), px.undefined, px.unattainable]

but not if I inline "una". Still more interesting:

        interpolate(qx, lx, ly, m, k) ==
            px := RationalInterpolation(lx, ly, m, k)$RIA(F, UP(xx, F))

            (px case "failed") => "failed"

            if ((qnum := retractIfCan(numer qx)@Union(F, "failed")) case F) and
               ((qden := retractIfCan(denom qx)@Union(F, "failed")) case F) then
              q := qnum/qden
              una := px.unattainable
              if any?(q::F=elt(lx, #1), px.unattainable) then return "failed"
--              for i in px.unattainable repeat
--                if elt(lx, i)=q then return "failed"

            [elt(px.function, qx), px.undefined, px.unattainable]

works!

Martin