0203 — Binding patterns are true wildcards, not NATS-style depth-precise matchers
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Context. A pattern language for binding.pattern had to be chosen.
NATS-style matching splits * (exactly one dot-delimited token) from >
(one-or-more trailing tokens), which can pin an exact hierarchy depth.
Decision. A true wildcard: * matches any run of characters at any
depth. wildcardToRegex translates a pattern to an anchored POSIX regex —
each * becomes greedy .*, literal segments are regexp.QuoteMeta-escaped.
Consequences. Depth is unpinnable: orders.*.central1 also matches the
deeper orders.us.high.central1, and there is no way to say “this many
segments, not more.” Traded deliberately for simplicity — nothing in the
system distinguishes “this depth” from “any deeper,” so the true wildcard
covers every real need so far. The depth-precise upgrade path is documented
as follow-up work rather than built speculatively.
Rejected: NATS-style */> — more expressive, but the expressiveness
had no consumer yet.