Listly

Lisp-style property lists and association lists for LFE.

Listly deliberately keeps the two representations separate:

• plist is a flat list of alternating keys and values, such as (:name "Alice" :age 30).
• alist is a list of two-item associations, such as ((name "Alice") (age 30)).

Both modules are implemented in LFE and expose ordinary BEAM modules that LFE or Elixir can call. The project includes the small mix_lfe-compatible compiler integration needed by current Mix and LFE releases.

Development

nix develop
mix deps.get
mix compile
mix test

The checked-in integration suite runs with mix test and calls the compiled LFE modules directly.

Semantics

Lookups are linear and return the first matching occurrence. Duplicate keys are retained. put replaces the first matching entry while preserving its position; absent entries are added at the front. remove removes every matching entry.

plist validates its input before every public operation. An odd-length or improper property list returns {error, malformed-plist}. alist:to-plist/1 returns {error, malformed-alist} when an entry is not a two-item list; other alist operations skip malformed entries during searches and collection.

Examples

(plist:get '(:name "Alice" :active false) ':name)
;; => "Alice"

(plist:put '(:name "Alice") ':age 30)
;; => (:name "Alice" :age 30)

(alist:assoc 'name '((name "Alice") (name "Bob")))
;; => (name "Alice")

(alist:pairlis '(name age) '("Alice" 30))
;; => ((name "Alice") (age 30))