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.
(defn compute [] i64 (handler-bind [...] (risky))) printed 0 through LLVM
and 2 through --x86, and neither was the restart's answer. The divergence
was real and the cause was in neither backend: check_handler_bind wrote
[ignore want] and typed the form Unit, so a unit in value position was
never checked against the expectation that would have refused it. Both
lowerings then answered a caller that had no business asking -- emit.ml a
literal zeroinitializer, x86.ml whatever the body's last form had left in
the destination slot. One of those looked like a value.
Unit was the wrong answer anyway. Every use of handler-bind in value
position in this repository -- restarts.flan, cleanup.flan,
p6-transfer.flan, p10-defer-transfer.flan -- writes it as a restart-case
body, where §3 requires the body and the clauses to agree in type; making
the form unit refuses all four. So it takes with-allocator's shape, which
is the same shape for the same reason: the body's last form is the value,
threaded through [expect] like any other. handler-case, whose value is the
handler's rather than the body's, is untouched and still refused by name in
parse.ml -- that difference is the whole of what separates the two, and it
is not this one.
emit.ml returns [last] with no phi and no slot: the pad terminates at
current_pad and never at the join, so the join has one predecessor and the
body's value dominates it. x86.ml needed no change at all -- it had been
passing dst and the type through to the body all along.
p12-handler-value.flan is the shape the survey could not see, plus the
neighbours a divergence usually travels with: a clause parameter, nested
restart-cases, a defer between the signal and the restart-case, and f64
and string across the transfer. All six already agreed; the handler-bind
value was alone. @x86 MATCH 128 -> 129, DIFFER 0.
