Rewrite deserialiseFromCBOR using asum with Alternative Maybe

[Copilot]

• Previous implementation using asum with Alternative Maybe
• Extract tryNativeScript named helper (point-free)
• Extract tryPlutusScript named helper (flat do-notation in Maybe monad)
• Replace maybe (Left ...) Right with maybeToRight combinator
• Replace either (const Nothing) Just with rightToMaybe combinator
• Extract error value as named noParseError constant
• Code review — no issues found

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[Copilot]

Just as a heads up, I was blocked by some firewall rules while working on your feedback. Expand below for details.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• chap.intersectmbo.org
  • Triggering command: /usr/bin/curl /usr/bin/curl REDACTED --output /tmp/transportAdapterGet4053-7 --location --write-out %{http_code} --user-agent cabal-install/3.16.1.0 (linux; x86_64) --silent --show-error --dump-header /tmp/curl-headers4053-8.txt (dns block)
  • Triggering command: /usr/bin/curl /usr/bin/curl REDACTED --output /tmp/transportAdapterGet4284-3 --location --write-out %{http_code} --user-agent cabal-install/3.16.1.0 (linux; x86_64) --silent --show-error --dump-header /tmp/curl-headers4284-4.txt (dns block)
  • Triggering command: /usr/bin/curl /usr/bin/curl REDACTED --output /tmp/transportAdapterGet4320-1 --location --write-out %{http_code} --user-agent cabal-install/3.16.1.0 (linux; x86_64) --silent --show-error --dump-header /tmp/curl-headers4320-2.txt (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

[carbolymer]

@copilot You are Alexis King. Rewrite your changes so that they are more readable, but avoid nesting and pattern matching.

[Copilot]

@copilot You are Alexis King. Rewrite your changes so that they are more readable, but avoid nesting and pattern matching.

Done in 6e1e76c. The logic is now split into three named helpers in the where clause:

• tryNativeScript — point-free: fmap (AnySimpleScript . SimpleScript) . L.getNativeScript
• tryPlutusScript — flat do-notation in the Maybe monad, no nesting
• noParseError — the error value, named and separated from the control flow

maybe (Left ...) Right → maybeToRight, either (const Nothing) Just → rightToMaybe (both from Data.Either.Combinators, already used elsewhere in the codebase). The main body reduces to two lines: decode the bytes, then try the parsers.