Yeah. The idea is that a tuple is immutable; once itís been constructed, it can no longer be modified. In that case, perl does know the extent of the data structure: itís the extent of the data structure at the time of its construction.
It would have more applications than just map, too. The ideaís not bad. (Of course it doesnít redeem the ST in my opinionÖ)
Makeshifts last the longest.