First end-to-end engine execution in tree: compile("ab")'s program
runs through skip-spawn / lit advance / match capture under the @test
drivers (search and the exec surface stay tranche C/D). Ported
Hare-verbatim from ref/hare/regex/regex.ha:589-742 — the #40 arg
wiring carries the ha:602 loop condition with no let-bind; arm bodies
stay verbatim so the group/repeat fold pastes straight into this
match. Arms compile() cannot emit are one loud not-yet-ported abort
each (the fold boundary); Hare's bare unreachable abort()s carry a
message because os.ww's private abort(msg) shadows the builtin
cross-module (filed, ww-core #45). The (anchored: bool)/(lit: rune)
casts are checker-required (ww aliases are nominal where Hare relies
on transparency), WHY-cited at site.
Hojun-Cho
e481cb86bd