Two provably-wrong cases the inference already has the facts for, closing the
last RFC 0006 open question:
- Calling a non-function. At an :invoke whose callee is provably :num or :str
(the only non-callable types — keywords/maps/vectors/sets are IFn), report
"cannot call a number as a function". Default level (no closed-world: the
callee type is inferred at the call site). Covers (5 1), ("hi" 0),
((+ 1 2) :k), a let-bound number, and a var holding a number (via vtype-box
in direct-link). A union is non-callable only when every member is, so
((if c 1 :k) x) is accepted (:kw is callable). Verified zero false positives
on the ray tracer, which calls maps/keywords/vectors as fns throughout.
- Wrong arity to a user fn. The registered single-fixed-arity sig (jolt-zo1)
makes a mismatched arg count provably throw; reported under the
JOLT_TYPE_CHECK_USER opt-in (same closed-world boundary; ^:redef/variadic
skipped). Caught at compile time before the runtime arity error.
Both fold into the existing infer walk, carry :pos for file:line:col, and keep
no-false-positives. Gate green, suite 4718, conformance 335/335, runtime bench
even (compile-time only).
Checking inherently needs an inference pass (~2.6x compile as a standalone
pass). But direct-link builds ALREADY run one inference pass for
specialization (run-passes' infer-top), so checking can ride along: set a
check-mode flag, turn checking? on during that existing pass, and collect
the diagnostics after — ~2% overhead measured on the ray tracer, vs 2.6x
for the separate pass.
So the checker now defaults to `warn` in direct-link builds (where it's
nearly free) and stays OFF in plain REPL/dev builds (no inference to ride,
no forced cost — opt in with JOLT_TYPE_CHECK there). JOLT_TYPE_CHECK still
overrides in both directions (off to disable, error to escalate).
It checks the POST-optimization IR, which matches what the optimized
program actually evaluates — scalar-replace only drops provably-pure code,
an accepted opt-mode divergence, so no real error is hidden. The loaders
enable position tracking whenever checking will run (env-selected or
direct-link). type-check! (the standalone pass) stays for plain builds;
both paths share report-diags!.
cli-test pins: plain build silent, direct-link warns by default,
JOLT_TYPE_CHECK=off disables. Gate green, suite 4718, runtime bench even.
rewrite-message assumed janet's BINARY arithmetic dispatch error shape
("could not find method :+ for 1 or :r+ for "a""). Unary inc/dec/- on a
non-number produce "could not find method :+ for "x"" — no "or :r" clause
— so orpos was nil and the reporter itself threw "could not find method :+
for nil", burying the real error. Handle the unary form. Found auditing
the RFC 0006 checker's default (checker-off) path. Regression row in
cli-test.
Syntax errors were positionless ('Unterminated list', no idea where).
Now they use Clojure's shape:
Error: Syntax error reading source at (src/app/syn.clj:3:8): Unmatched delimiter: ]
at src/app/top.clj:1
The reader's 15 error sites raise a {:jolt/reader-error :msg :pos}
struct carrying the byte offset (every site already had pos in scope).
The parse entry points convert offset -> line:col on demand and
re-raise the formatted message: parse-string against its own string
(no file), parse-all-positioned against the full source with the
file threaded in from the loaders — rebasing slice-relative offsets
onto the original source so positions stay absolute. No per-token
cost; nothing is tracked until an error actually happens.
Unmatched-delimiter messages match Clojure's 'Unmatched delimiter: )'
wording. cli-test rows assert positions for unterminated string/list,
unmatched delimiter through a require (composing with round 4's
'while loading' chain), and bad ## tokens. Gate green, suite 4718
steady, bench within noise.
A failing top-level form now reports where it lives:
Error: Cannot add 1 and "boom" — + expects numbers
at /path/src/app/broken.clj:3
while loading /path/src/app/mid.clj
while loading /path/src/app/top.clj
The reader has no per-form positions (round 5), but the loaders know
exactly which slice of source each form came from: parse-all-positioned
(reader) counts newlines around parse-next and returns [form line]
pairs; load-ns, load-string and load-ns-source evaluate through a
positioned loop that on error stashes the innermost form's {:file
:line} on the env and appends each file unwound through to a loading
chain. report-error prints both, suppressing the synthetic <eval>
strings the CLI feeds itself (the require/apply one-liners).
load-string takes an optional file arg; run-file passes the script
path so script errors name the script. cli-test rows cover the
3-requires-deep case, script files, and that one-line -e output stays
clean. Gate green, suite 4718 steady, bench within noise.
A typo'd symbol used to auto-intern an unbound var and die later as
'Cannot call nil as a function' with no hint which symbol. Now:
$ jolt -e '(undefined-fn 1)'
Error: Unable to resolve symbol: undefined-fn in this context
The analyzer's :unresolved fallthrough now punts to the interpreter
(whose resolver raises the message above when the form runs) instead of
emitting a var-ref that interned the var. A punt rather than a hard
throw because runtime-interning forms (defmulti's setup) legitimately
reference the var they're about to create from a nested do.
Pulling that thread surfaced three real bugs the leniency was masking:
- h-resolve-global resolved unqualified symbols against ctx-current-ns,
which during analysis is jolt.analyzer — so user-ns vars NEVER
resolved through it; the lenient arm happened to emit the right ns.
Now resolves against the compile ns like the qualified branch.
- Top-level (do ...) wasn't split: Clojure compiles and EVALS each
child in sequence so earlier children's runtime effects (defmulti's
intern) are visible while later children compile. eval-toplevel now
splits.
- The stdlib itself had forward references the auto-intern hid:
10-seq's transducers used vreset!/vswap! from 20-coll (moved to
10-seq); in 20-coll qualified-ident?/realized?/list*/underive
referenced defs declared later in the file (reordered); sorted? and
partition-all are genuinely later-tier and got (declare ...).
Test rows updated where they encoded the old leniency: ir-passes'
dead-branch row (unresolved in a dead branch is an error, as in
Clojure), compile-mode's ctx-isolation row (other ctx now errors
instead of reading nil), cli rows assert the new message. Gate green,
conformance 335/335 x3, suite 4718 steady, bench within noise.
Before: (+ 1 "a") printed 'could not find method :+ for 1 or :r+ for "a"'
followed by three janet frames pointing at jolt internals. After:
Error: Cannot add 1 and "a" — + expects numbers
at app.deep/level3
Round 1 — compiled fns carry their Clojure identity:
- The analyzer's recur target (which doubles as the compiled janet fn's
name) is now ns/fn-name (_r$app.deep/level3--N), so janet stack traces
name the user's fns; defn passes the self-name through to fn.
- eval-toplevel re-raises with propagate instead of protect+error — the
failing fiber's stack was being discarded, which is why every trace began
at eval-toplevel.
- require/maybe-require-ns route loaded namespaces through the loader's
compile-or-interpret eval-toplevel via a ctx hook (the evaluator can't
import the loader). Previously REQUIRED namespaces always ran interpreted:
slower, and their fns were anonymous in traces.
Round 2 — report-error presents for users (rephrase-inspired):
- The full trace text is stashed at the innermost eval-toplevel boundary
(janet's debug/stacktrace walks the fiber propagation chain; debug/stack
cannot), then filtered: _r$ frames demangled to ns/fn-name, jolt-internal
and [eval] frames dropped. JOLT_DEBUG=1 restores the raw janet trace.
- Message rewrites: janet arithmetic dispatch -> 'Cannot add X and Y — +
expects numbers'; compiled arity -> Clojure's 'Wrong number of args (N)
passed to: ns/fn'; nil-call gets an undefined-symbol hint (round 3 will
fix resolution properly).
6 cli-test rows assert the exact user-visible output. Gate green, suite
4718 steady, bench within noise.
Add --version/version, -e/--eval, -f/--file, -m/--main (require NS and apply
its -main to *command-line-args*), and nrepl-server/--nrepl-server taking an
optional [host:]port (nrepl stays an alias). repl/help/-h round it out.
Also rewrite doc/tools-deps.md as design notes for the now-implemented deps
support (it still read as pre-implementation research), and note the new flags
in the README. Test: cli-test runs the flags from source.
