erlang: gen_server behaviour (+10 tests)

lib/erlang/transpile.sx

@@ -486,10 +486,10 @@
             (er-apply-fun (get env name) vs)
             :else (er-apply-bif name vs)))
         (= (get fun-node :type) "remote")
-        (er-apply-remote-bif
-          (get (get fun-node :mod) :value)
-          (get (get fun-node :fun) :value)
-          (er-eval-args args env))
+        (let
+          ((mod-name (er-resolve-call-name (get fun-node :mod) env "module"))
+            (fn-name (er-resolve-call-name (get fun-node :fun) env "function")))
+          (er-apply-remote-bif mod-name fn-name (er-eval-args args env)))
         :else
         (let
           ((fv (er-eval-expr fun-node env)))
@@ -509,6 +509,24 @@
         (range 0 (len args)))
       out)))
 
+;; Resolve a remote call's module/function reference into a string.
+;; Atom AST nodes use their `:value` directly. For any other shape
+;; (typically a var or another expression), evaluate it and require
+;; the result to be an atom.
+(define
+  er-resolve-call-name
+  (fn
+    (node env kind)
+    (cond
+      (= (get node :type) "atom") (get node :value)
+      :else (let
+        ((v (er-eval-expr node env)))
+        (if
+          (er-atom? v)
+          (get v :name)
+          (error
+            (str "Erlang: call " kind " must be an atom, got " (er-format-value v))))))))
+
 ;; ── fun values ───────────────────────────────────────────────────
 (define
   er-mk-fun