Applied Pokology: Array boundaries and closures in Poke

Poke arrays are rather peculiar. One of their seemingly
bizarre characteristics is the fact that the expressions
calculating their boundaries (when they are bounded) evaluate
in their own lexical environment, which is captured. In other
words: the expressions denoting the boundaries of Poke arrays
conform closures. Also, the way they evaluate may be
surprising. This is no capricious.