feat: add entry-embeds matcher for predicate map keys (#132)

[felipeofdev-ai]

Summary

Implements philomates' opt-in approach from #132: a new entry-embeds matcher for maps whose keys and/or values should be matched with predicates or submatchers.

Default map matching is unchanged — literal keys only. Predicate keys like {keyword? :b} still do not match {:a :b} unless wrapped in entry-embeds.

Fixes #132 (opt-in path; documents limitation for default maps)

Design

Following philomates' suggestion, map matching with predicate keys is recast as order-agnostic matching over [key-matcher value-matcher] entry pairs:

(is (match? (m/entry-embeds [[keyword? odd?] [:x pos?]])
            {:a 1 :x -1 :whatever "foo"}))

;; Duplicate key matchers (impossible in literal maps):
(is (match? (m/entry-embeds [[symbol? 2] [symbol? 1]])
            {'x 1 'y 2}))

Extra entries in the actual map are ignored (embeds semantics). Runtime is the same class as embeds / in-any-order — documented warning for large maps.

Changes

• EntryEmbeds record + entry-embeds public matcher
• Regression tests covering match? mismatches predicates when applied to keys in maps #132 REPL examples + philomates multi-entry case
• README: documents entry-embeds and notes default map behaviour

Test plan

• New unit tests in core_test.clj and matchers_test.clj
• Maintainer CI (Nu workflows)

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— Felipe Fernandes · Systems & Agentic AI Engineer
https://github.com/felipeofdev-ai · https://felipeofdev-ai.github.io/