Regex literals and new RegExp calls accept the v (unicode sets) flag, which
the vendored engine implements: class subtraction and intersection, nested
classes, \q{...} string literals and properties of strings. The flag uses
unicode mode for pattern decoding and string iteration, and flags read in
getter order (dgimsuvy). Regex literals now also report their flags in
getter order, as Node does for /x/yg, and the flag getters (global,
unicodeSets and the rest) compile on statically typed regexes.
In v mode the engine rejected `-` and doubled punctuation outside a
character class, and the `\-` escape inside \q{...}. It now applies the
class-only checks inside classes and \q{...} only, and parses \q{...}
contents with the class escapes, matching Node. The d flag is still
refused.
* Expand static compilation for common Effect 4 patterns
* Run every Effect 4 fixture slice in CI
* Preserve existing corpus behavior across Effect 4 lowering
* Preserve Effect platform callbacks and native stream state
* Record new corpus baselines and retain child stdin refusals
* Retire the obsolete stateful regex diagnostic
* Preserve promise reference count layout for cycle collection
- lowerRegexLiteral drops the (?<name> fence: patterns and \k<name> backreferences run natively in libregexp, and .groups on exec/match/matchAll results desugars into a compile-time record projection over the honest slice — the checker's own Record<string,string> hybrid with overflow entries in group declaration order — whenever the regex is statically known (literals, const bindings, new RegExp("..."), matchAll rows via for-of bindings, stored drains, spread rows, element access)
- Node's exact shapes: a group-less regex answers .groups === undefined, nullable receivers throw Node's TypeError on the unit arms, ES2025 duplicate names project the participating alternative, and destructuring rides — flat, aliased, and the nested { groups: { year } } pattern — via the groups wrap plus a general overflow read for undeclared keys of index-signature shapes
- scr_put_substitution resolves $<name> against lre_get_groupnames with Node's edge answers: nonexistent and nonparticipating names substitute empty, $< stays literal when the pattern has no named groups, an unterminated $<name stays literal
- s.match(re) also claims a nullable string receiver (the Dict<string> member spelling) through the checked narrow; an untraceable .groups read keeps the SC2020 fence with a hint naming the traceable shapes
- Differential corpus 2604-2607 (both backends, SAN), runtime C substitution/backreference cases, refreshed diagnostics snapshots and surface manifest; corpus 1614's deliberate deferred fence moves to a Proxy wrap now that hybrid record reads compile
- island ('any') arguments at intrinsic/libCall/callValue slots take the validated exit (dynCheck's stance); non-exit-safe slots fence with the slot named, and the boundary pass backstops every jsOp/dynCall/dynInvoke argument so world-mixing sites can never ICE
- a checker-'any' receiver/callee that LOWERED checked-dynamic dispatches to the DOM machinery: ambient-this reads are dynKeyGet, rest-args map/forEach ride the runtime dispatch, dyn callees take dynCall
- Object.entries/values push unit-armed (null | undefined) fields as the null literal; new Set(seed) exits an island-handle seed as a validated copy
- fence-bodied functions emit even when their ABI names an unregistered class, and a run()-end sweep rewrites leftover unregistered-class type slots to the inert f64 placeholder — the clang invalid-C escape closes with the ICE
- RegExp[] compiles (REF elements, both backends; map callbacks returning other unrepresentable kinds meet a named fence), and the C emitter appends program-sized line arrays by loop, not spread (500k-line TUs overflowed the stack)
Chris Tate