The trio the author decided on 2026-09-20 is now all built: def is CL's
defparameter — its initialiser runs on every daemon re-run, unguarded, so
an edited initialiser repaints the same storage on C-c C-c plus re-run —
defonce (Clojure's name for CL's defvar, per the author) initialises once
behind the .init~once. flag, and defconst stays the image.
One parse arm reads both forms; the difference is Ast.reinit, carried to
Tast.global's grerun. Emit.startup_plan gives a def no guard flag, and
Check.check_global lifts every def initialiser — zero and literal
included — into global/<n>, so the host's startup reaches it through the
function cell and a re-evaluated def swaps it (Session's def_inits;
Emit.redefinition declares the cell for a non-sibling target). The old
defvar spelling is refused with the rename and both compiling spellings,
and every program, test, doc and editor list is swept — except sand.flan,
the author's live WIP, whose seven defvar lines are flagged in FIX.org
and keep its three dependent tests red on this branch.
The dyn runtime gets a map object and an interned keyword, alongside the
vec it already had. {:a 1 :b s} is a map literal wherever a struct
literal isn't — the parser tells the two apart by whether the first form
in the braces is a .field symbol — and a bracket literal builds the
runtime's own vec rather than a typed array wherever a dyn is wanted, which
is what lets a map literal's values nest arrays and maps freely. get, put,
len and has-key? all learn a dyn-map arm alongside the typed-map one they
already had, and (keyword s) builds the same interned value a :foo literal
does, for a name that only exists at run time. nil is now a literal, the
dyn absence value that get answers for a key a map does not hold.
On the runtime side, flan_dyn.c gets an OBJ_MAP that shares the vec's
storage arm and doubles its accounting, a linear-scan intern table for
keywords that makes equality an identity compare, and structural map
equality by lookup rather than position. The marker traces a map's
interleaved keys and values the same way it already traced a vec.
edn/read and its callers move off the old (Option Value) union entirely:
a document is plain dyn now, sets are dyn maps to true, and arena-edn.flan
is retired along with the union it demonstrated. The acceptance suite's
edn-read and json rows were recaptured against the new shape, and a new
dyn-map.flan program exercises the map and keyword operations end to end,
including a 200k-iteration churn loop against a rooted map that runs
GC for real, across the LLVM, -O0 and x86 rows, and under the sanitizer.
Keywords are dyn everywhere an enum isn't expected, which changed what a
couple of existing checker tests actually see refused; both were updated
to the sentence the checker gives now rather than the one it used to.