The results of a for so far, for a body that only indexes partial (partial[i - 1], count(partial)).

A body that reads partial as a list is given a list of the results, made again for each iteration: m cells for the mth result, m * m / 2 for a loop of m, and a read partial[k] is k steps in it (D-86, D-154). A body whose every read is an index or a count (Feel.Analysis.Iterations.view/2) is given these results instead: an array that the loop puts each result in, as it makes it, and that the reads look in. A result costs a few steps to put in, a read costs a few steps whichever result it is of (the first, the last, the one in the middle), and the count is the size. The array is a value that a result does not change (:array is functional), so the body keeps the one it was given, as it kept its list.

The reads give what Feel.Runtime.Filter.at/4 gives for the list of the results, for any index: the same value, the same diagnostic and the same span. A newest-first list and its count would do for the reads of the last results, and not for partial[1], which is as far from the newest as the loop is long.

iex> results = Enum.reduce([10, 20, 30], Feel.Runtime.Partial.new(), &Feel.Runtime.Partial.push(&2, &1))
iex> Feel.Runtime.Partial.to_list(results)
[10, 20, 30]
iex> env = Feel.Runtime.Env.new()
iex> {value, _env} = Feel.Runtime.Partial.at(env, results, Decimal.new(-1), {0, 10})
iex> value
30
iex> {count, _env} = Feel.Runtime.Partial.count(env, results, {0, 14})
iex> Decimal.to_integer(count)
3