Parser: parse-on-feat now consumes `first` keyword before event-name (sets
count-min/max to 1) and a count expression after event-name — `N` (single),
`N to M` (range), `N and on` (unbounded above). Number tokens are coerced
via parse-number. Emits :count-filter {"min" N "max" M | -1} part.
Compiler: scan-on threads count-filter-info; the handler binding wraps the
fn body in a let-bound __hs-count counter. Each event fire increments the
counter and (when count is in range) executes the original body. Each
on-clause registers an independent handler with its own counter, so
`on click 1 ... on click 2 ... on click 3` produces three handlers that
fire on their respective Nth click (mix-ranges test).
Generator: dropped 5 cluster-34 tests from skip-list — `can filter events
based on count`, `... count range`, `... unbounded count range`, `can mix
ranges`, `on first click fires only once`.
hs-upstream-on: 43/70 → 48/70. Smoke 0-195 unchanged at 172/195.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
giles
19c97989d7