| name | phel-lang |
| description | Write or verify Phel code (Lisp on PHP). Triggers on .phel files, phel-config.php, phel CLI commands, or Phel snippets in markdown docs. Verify any non-trivial snippet against the runtime before claiming it works. |
| model | sonnet |
Phel
Lisp dialect compiling to PHP. Persistent data structures. PHP interop via php/.
Verify before documenting
Any Phel snippet added to docs/blog/cookbook MUST be runtime-checked. Examples that "look right" silently rot. Two ways:
./vendor/bin/phel run -e '(println (map inc [1 2 3]))'
./vendor/bin/phel repl
Write the snippet, run it, paste real output. If output differs from what you assumed, fix the doc - not the runtime.
Gotchas (project-specific)
defprotocol cannot be implemented inline in defstruct. Use definterface for inline; defprotocol + extend-type per struct.extends? works only on primitive type keywords (:string, :int). Returns false for struct types. Use satisfies? on instances instead.- CLI args:
argv (vector of user args, excludes program name); *program* for the script path. Not *argv* or php/$argv.
- Side effects:
doseq / foreach. Build sequences: for. Mixing causes wrong return shape.
- String module:
phel\string (not phel\str).
- Phel vectors print as
@[...]. Clojure prints [...]. Match the runtime output in docs.
Core syntax
(defn greet [name] (str "Hello, " name)) ; function
(defrecord Todo [id text done]) ; record (positional + map ctor)
(definterface Showable (show [this])) ; interface - inline-implementable
(defprotocol Renderable (render [this])) ; protocol - extend-type only
(extend-type Todo Renderable (render [t] ...)) ; protocol impl per type
(defmulti area :shape) ; multimethod
(defmethod area :circle [{:radius r}] (* 3.14 r r))
(into [] (comp (filter odd?) (map inc)) [1 2 3 4 5]) ; transducer
(re-find #"\d+" "abc123") ; regex literal
PHP interop
(DateTimeImmutable. "2026-01-01") ; constructor shorthand
(.format obj "Y-m-d") ; method shorthand
(.-prop obj) ; property shorthand
DateTimeImmutable/ATOM ; static constant
(DateTimeImmutable/createFromFormat ...) ; static method
(php/strlen "x") ; any PHP function
This repo
- Docs:
content/documentation/, content/blog/
- Phel scratch:
local/main.phel
- Build artifacts:
build/phel-config.php, .phel/
- CLI:
./vendor/bin/phel <run|repl|test|build>
For full language reference: content/documentation/language/ and content/documentation/reference/.
