The reason given was wrong. A dot path did reach an empty-named field:
Fake("a.") returned it, Fake("a.b.") returned a nested one, and {..a.} bound
it. What was true is narrower — List never offered it, because an empty name
is no path segment — so the engine accepted spellings it would not advertise.
The message, the test comment and the README say that instead.
Two things the rejection finished off:
A {} token still reported "no field \"\"", pointing at a fix the loader now
rejects — two errors for one rule. It is told the name can never exist, like
an option token already is.
addressable is dead: both halves of "not empty and no dot" are now rejected
where a name is authored. Mutating it to panic leaves the suite green here
and panics on main, so it was live and is not. Keeping it would preserve the
silent-hiding this change removes — List quietly omitting a name rather than
New refusing it.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
A field named "" was reachable by exactly one spelling, a bare {} token,
and by no dot path: List hid it and Fake could not ask for it. checkName
rejects it now, for the reason it rejects a dot — a name no path can reach.
That also makes the empty-segment rule unconditional. {a.} was rejected
because a field really named "" would otherwise have made it resolve; no
data can carry one, so the rule now guards a shape that cannot exist.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The operand order was written out in three places; it now lives at calcVars,
which fixes it, and the other two point there. Dropped the note explaining
why ')' is not reserved, which said what the set is not rather than what it
is, and shortened reservedList's doc to less than its body. The note on held
now states where it reaches instead of arguing against a design this repo no
longer contains.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
A field the format rendered and a calc read was drawn twice, so the operand
shown could differ from the operand computed — the same disagreement the
dotted-path rule already fences, in its plainest spelling. The README
carried it as a caveat, which is what a rule like this exists to remove.
A calc operand now joins the names an expansion holds, so it is drawn once
and every later read of it — the calc, and any bare token spelling it —
sees that draw. The hold stays per expansion: each repeat iteration and each
nested template draws its own.
expand reads a calc's operands before the call and hands over their values,
so a builtin takes (emitted, operands) rather than the sibling fields, and
the evaluator indexes that slice instead of walking the node tree. That is
what keeps the draws a local. Handing them to a builtin instead lets them
escape through an indirect call, which put two maps on the heap for every
held format, calc or not: BenchmarkBound went 56 B/5 allocs -> 744 B/10.
Measured against main: Bound 359 -> 349 ns at 56 B/5 allocs, unchanged;
Calc 416 -> 577 ns and one more alloc, which is what the correlation costs.
Validation is unchanged: t.bound still carries only the levels a dotted
token reads, so the overlap fences fence exactly what they did.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The dot rule was spelled twice — once for a category or folder, once for a
field — and covered only the dot. Both now go through checkName, which
rejects the four characters no format can name: . | ( and }.
')' stays legal: on its own it is spellable, and rejecting it would refuse a
name that works.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
lilleman
M
Mikael Göransson