The author: "I think I prefer length over len, because then I'll use len as
the variable name". One arm in check.ml, one row in the table beside it, and
every (len x) in lib, test, examples, vendor, spike, docs, web, emacs,
plan.org and NEXT.md rewritten.
Shadowing and builtin/ had already taken most of the sting out: a (defn len
...) was legal and won in its own file, and builtin/len reached past it. What
was left is that len was still a builtin — the defn earned a warning, and a
wrapper had to say builtin/ at every inner call. Now there is nothing under
the short name: len is an ordinary identifier in every position, which is
what (let [len (length xs)] ...) wants.
length takes over as shadowing's worked example rather than the feature
losing one. shadow-builtin.flan, builtin-qualified.flan, pkgs/shadowed and the
builtin/ rows in test_flan move to it and go on testing shadowing.
A call to a len nothing defines is answered where an unknown function is,
after every table and after the shadowing guard, so a program with its own len
never reaches it. The sentence is said rather than guessed at — len and length
are three edits apart and the did-you-mean's net is one — and the call is
written back out through spell_arg, as-slice's spelling lifted out of it and
now shared, so what is printed compiles.
sand.flan:33 still calls the old name and is the author's to change; until it
does, test_acceptance and test_session abort there. Both were run green
against a copy with that one line changed. FIX.org says so.
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.
Another lane landed (slice-from-ptr p n) while this backend was not looking,
and it arrived as two refusals rather than one: slice-from-ptr.flan and
bounds.flan both stopped building through --x86. Neither is a new obstacle —
a Slice _ is {ptr, i64} here exactly as it is in emit.ml, so the form is one
store of the pointer and one of the length and no new representation at all.
The half worth writing down is the check. There is nothing to compare the
length against — only the caller knows how many elements live behind that
pointer — so what is checked is that the promise is not absurd, and that test
is *signed*. check_slice's own compares are unsigned, and a negative i32
sign-extended to 64 bits is a huge unsigned value that an unsigned "hi <= len"
waves through; the result would be a slice about 2^64 long that reads as a
pass and faults somewhere else entirely.
Nothing in the corpus walks that path: every length in slice-from-ptr.flan is
a literal, and a negative literal is refused by check.ml before any code is
emitted. So spike/x86/p7-slice-from-ptr.flan takes the length as a parameter
and runs it through a restart-case, which puts the condition's low/high/length
on stdout and compares them against the LLVM build.