-- Reserved short builtin names cannot be reused as binding or function
-- names. The parser rejects `ct=...`, `avg=...`, `flat=...`, etc. at the
-- declaration site with ILO-P011 + a rename hint, so the agent's first
-- retry is the right one (rather than a silent mis-dispatch surfacing as
-- a confusing ILO-T006 arity error at the use site).
--
-- WOULD ERROR — `ct` is a v0.11.6 builtin (count-where):
-- main>n;ct=10;ct
-- -- ERROR ILO-P011: `ct` is a builtin and cannot be used as a binding name
-- -- hint: rename to something like `myct` or `ctv`.
--
-- WOULD ERROR — `avg` is a builtin (mean of a list):
-- main>n;avg=/sumd n;avg
-- -- ERROR ILO-P011: `avg` is a builtin and cannot be used as a binding name
-- -- hint: rename to something like `myavg` or `avgv`.
--
-- Safe strategies (full list + forecast: SPEC.md > Reserved namespaces):
-- * pick an unreserved 2-char name (`cty`, `mn`, `ix`, `pq`, ...)
-- * append a vowel or suffix (`ctv`, `avgv`)
-- * use a 4+ char name (always safe across future releases)
--
-- This example uses 4-char `mycnt` as the local count accumulator —
-- guaranteed forward-compatible because new ilo builtins land under
-- names of 4 characters or longer.
main>n
xs=[1 2 3 4 5]
mycnt=ct (x:n>b;>x 2) xs
mycnt
-- run: main
-- out: 3