diff --git a/TODO.org b/TODO.org
index d8558474..4082966a 100644
--- a/TODO.org
+++ b/TODO.org
@@ -1078,6 +1078,10 @@ should not pay for identity and metadata. Not implemented.
 function nosuch" twice at the same place and counts 2 errors — once from the
 abstract pass and once from the instantiation.
 
+** TODO A type variable is printed without its $
+=Types.to_string= prints =Var t= as =t=, so a refusal reads "selection-sort
+expects [t] here, found [3 i32]" where the source wrote =[$t]=.
+
 ** DONE Two refusals suggested something that does not compile
 CLOSED: [2026-09-25]
 =vec-new= and =map-new= with no type no longer say "or give the binding a type";
@@ -1086,11 +1090,16 @@ An unknown call whose near miss is a value — =(context-allocator)= against
 =context/allocator=, or a global — says the name is a value written without
 parentheses, and names no call at all when the call had arguments.
 
-** NEXT (max-of T) and (min-of T)
+** NEXT (max-value T) and (min-value T)
 Decided 2026-09-25: the type-limit constants as a form taking a type, Odin's
 max(T), valid at any numeric type or a numeric?-bounded variable. For a float,
 min-of is the most negative finite value.
 
+** NEXT (Ptr const T), the pointer beside [const T]
+Decided 2026-09-25: addr through a read-only slice gives a (Ptr const T), which
+nothing writes through; (Ptr T) widens to it and never back; a C parameter
+declared const T* takes one. Closes the addr hole in [const T].
+
 * Backends
 
 ** DONE The x86 backend tracks LLVM at -O0
@@ -1270,6 +1279,13 @@ lowering buffer annotates all four sections, the two =llc= ones from a =--debug=
 copy of the IR. Rules out writing a disassembler, and reading the source off disk
 at disassembly time.
 
+** NEXT A temporary allocator, wiped each frame
+Decided 2026-09-25: Odin's context.temp_allocator. i64->bytes, f64->bytes and
+other quick formatting allocate from it, so a number drawn every frame no longer
+leaks from the default allocator. A dev build wipes it at each frame boundary;
+otherwise the program calls (free-temp) once per frame. Text kept past the frame
+is cloned.
+
 * Runtime
 
 ** DONE An index out of range is a condition
@@ -1931,6 +1947,11 @@ C-x C-e thunk triggered. Needs reproducing under load and fixing.
 
 * Editor
 
+** TODO C-c C-l on a generic needs a session to find its copies
+The lowering view compiles the file, but only the daemon's =defs= says which
+functions are a generic's copies, so with no session a generic's name shows
+nothing. Needs a way to ask the compiler for a file's copies of a name.
+
 ** DONE The syntax table and the font-lock lists are read off the parser
 CLOSED: [2026-09-21]
 The special-form list is the heads the parser dispatches on, the builtin list is
diff --git a/emacs/flan-lower.el b/emacs/flan-lower.el
index 1fe0f6c9..4fdd3268 100644
--- a/emacs/flan-lower.el
+++ b/emacs/flan-lower.el
@@ -415,6 +415,40 @@ looks like."
             (buffer-substring-no-properties beg (line-beginning-position 2))
           (buffer-substring-no-properties beg (point-max)))))))
 
+(defun flan-lower--copies (name)
+  "The names of the copies of generic NAME the connected program has, or nil.
+A generic has no code under its own name: each type it is called at makes a
+copy named for the types, `selection-sort-i32'.  The daemon lists the generic
+with its signature as written, `$' and all, and lists each copy with the
+generic's own location -- which is what tells a copy from an unrelated
+function that happens to share the prefix, `sort-bytes' beside `sort'."
+  (let ((g (assoc name flan--defs)))
+    (when (and g (string-match-p "\\$" (nth 2 g)))
+      (let ((prefix (concat name "-")))
+        (sort (mapcar #'car
+                      (seq-filter
+                       (lambda (d)
+                         (and (string-prefix-p prefix (car d))
+                              (equal (nth 1 d) "fn")
+                              (equal (nth 3 d) (nth 3 g))))
+                       flan--defs))
+              #'string<)))))
+
+(defun flan-lower--fetch-copies (section name)
+  "SECTION for each copy of generic NAME, each under a line naming it, or nil.
+The copies are the session's, and the file may call the generic at fewer
+types than the session does; a copy the file does not make is named as such
+rather than left out."
+  (let ((copies (flan-lower--copies name)))
+    (and copies
+         (mapconcat
+          (lambda (c)
+            (format ";; %s\n%s" c
+                    (or (funcall flan-lower-fetch-function
+                                 section flan-lower--file c flan-lower--flags)
+                        "not made by this file: nothing in it calls at these types\n")))
+          copies "\n"))))
+
 (defun flan-lower--gather (sections)
   "Fetch each of SECTIONS into `flan-lower--texts', replacing what was there.
 One section's failure is that section's text and not the buffer's: `llc' can
@@ -425,6 +459,7 @@ altogether would be the wrong answer to that."
                     (or (funcall flan-lower-fetch-function
                                  s flan-lower--file flan-lower--name
                                  flan-lower--flags)
+                        (flan-lower--fetch-copies s flan-lower--name)
                         (format "nothing for `%s' here\n" flan-lower--name))
                   (error (concat (error-message-string err) "\n")))))
       (setf (alist-get s flan-lower--texts) text))))
diff --git a/emacs/flan.el b/emacs/flan.el
index 0f60efd1..2b9b8aad 100644
--- a/emacs/flan.el
+++ b/emacs/flan.el
@@ -3029,36 +3029,72 @@ tail of exactly one packaged name, because a buffer inside a package writes
       (let ((inhibit-read-only t))
         (erase-buffer)
         (flan-disassembly-mode)
-        (let ((start (point)))
-          (insert (format "; %s for %s\n"
-                          (if ir "LLVM IR" "disassembly") full))
-          (put-text-property start (point) 'face 'font-lock-comment-face))
-        (flan-disassemble--header "signature" (plist-get r :signature))
-        (flan-disassemble--header "source" (plist-get r :loc))
-        (flan-disassemble--header
-         "generation"
-         (let ((g (plist-get r :generation)))
-           (if (and (numberp g) (zerop g))
-               "0 (the build the program was launched from)"
-             (format "%s" g))))
-        (flan-disassemble--header "object" (plist-get r :object))
-        (flan-disassemble--header "showing" (plist-get r :basis))
-        (when (plist-get r :note)
-          (flan-disassemble--header "note" (plist-get r :note)))
-        (insert "\n")
-        (let ((start (point)))
-          (insert (plist-get r :text))
-          ;; The source lines the daemon placed in the listing, and the
-          ;; headings in the IR, are `;' comments; shown as comments so the
-          ;; code between them reads as the code.
-          (save-excursion
-            (goto-char start)
-            (while (re-search-forward "^[ \t]*;.*$" nil t)
-              (put-text-property (match-beginning 0) (match-end 0)
-                                 'face 'font-lock-comment-face))))
+        (flan-disassemble--render r (if ir "LLVM IR" "disassembly"))
         (goto-char (point-min))))
     (display-buffer flan-disassembly-buffer)))
 
+(defun flan-disassemble--comment (text)
+  "Insert TEXT as a line drawn as a comment."
+  (let ((start (point)))
+    (insert text "\n")
+    (put-text-property start (point) 'face 'font-lock-comment-face)))
+
+(defun flan-disassemble--render (r what)
+  "Insert the reply R into the current buffer; WHAT names the view.
+A generic has no code of its own, only a copy per type it was called at.
+The daemon answers its name with that copy's listing when there is one, and
+with `:copies', one listing each, when there are several; each is headed by
+the types its variables were bound to."
+  (let ((copies (plist-get r :copies)))
+    (if copies
+        (progn
+          (flan-disassemble--comment
+           (format "; %s for %s, one copy per type it is called at"
+                   what (plist-get r :name)))
+          (flan-disassemble--header "signature" (plist-get r :signature))
+          (dolist (c copies)
+            (insert "\n")
+            (flan-disassemble--comment
+             (format ";; %s at %s" (plist-get c :generic) (plist-get c :types)))
+            (if (plist-get c :refused)
+                (progn
+                  (flan-disassemble--header "signature" (plist-get c :signature))
+                  (flan-disassemble--header "no listing" (plist-get c :refused)))
+              (flan-disassemble--listing c))))
+      (flan-disassemble--comment
+       (if (plist-get r :generic)
+           (format "; %s for %s at %s" what (plist-get r :generic)
+                   (plist-get r :types))
+         (format "; %s for %s" what (plist-get r :name))))
+      (flan-disassemble--listing r))))
+
+(defun flan-disassemble--listing (r)
+  "Insert one function's headers and listing out of the reply R."
+  (flan-disassemble--header "signature" (plist-get r :signature))
+  (flan-disassemble--header "source" (plist-get r :loc))
+  (flan-disassemble--header
+   "generation"
+   (let ((g (plist-get r :generation)))
+     (if (and (numberp g) (zerop g))
+         "0 (the build the program was launched from)"
+       (format "%s" g))))
+  (flan-disassemble--header "object" (plist-get r :object))
+  (flan-disassemble--header "showing" (plist-get r :basis))
+  (when (plist-get r :note)
+    (flan-disassemble--header "note" (plist-get r :note)))
+  (insert "\n")
+  (let ((start (point)))
+    (insert (plist-get r :text))
+    (unless (bolp) (insert "\n"))
+    ;; The source lines the daemon placed in the listing, and the headings in
+    ;; the IR, are `;' comments; shown as comments so the code between them
+    ;; reads as the code.
+    (save-excursion
+      (goto-char start)
+      (while (re-search-forward "^[ \t]*;.*$" nil t)
+        (put-text-property (match-beginning 0) (match-end 0)
+                           'face 'font-lock-comment-face)))))
+
 ;;;###autoload
 (defun flan-disassemble-ir (name)
   "Show the LLVM IR NAME's installed body was built from.
diff --git a/emacs/test-flan.el b/emacs/test-flan.el
index 762551ed..c0938cd2 100644
--- a/emacs/test-flan.el
+++ b/emacs/test-flan.el
@@ -1822,6 +1822,44 @@ already rely on it — so nothing here is a stand-in for the real thing."
                           (user-error (setq raised (error-message-string err))))
                         (and raised (string-match-p "not a function" raised))))
 
+    ;; A generic has no code under its own name, only a copy per type it is
+    ;; called at, so its name is answered with those: refused while there are
+    ;; none, and one listing per copy, each headed by its types, once there
+    ;; are several.  Sent from a file that is not the program's.
+    (let ((file (concat socket3 "-sorts.flan")))
+      (flan--request
+       (list :op "eval" :file file
+             :code "(defn selection-sort [xs [$t]] ()
+  {:where (ordered? $t)}
+  (dotimes [i (length xs)]
+    (let [m i]
+      (dotimes [j (length xs)]
+        (when (< (at xs j) (at xs m)) (set m j)))
+      (swap xs i m))))"))
+      (test-flan--check "a generic nothing calls yet is refused, saying why"
+                        (let ((raised nil))
+                          (condition-case err (flan-disassemble "selection-sort" t)
+                            (user-error (setq raised (error-message-string err))))
+                          (and raised
+                               (string-match-p "is generic" raised)
+                               (string-match-p "no code has been made" raised))))
+      (flan--request
+       (list :op "eval" :file file
+             :code "(defn use-sort [] ()
+  (let [a [3 1 2]] (selection-sort (slice a 0 3)))
+  (let [b [3.0 1.0]] (selection-sort (slice b 0 2))))"))
+      (flan-disassemble "selection-sort" t)
+      (with-current-buffer flan-disassembly-buffer
+        (let ((text (buffer-string)))
+          (test-flan--check "a generic's IR is shown copy by copy"
+                            (and (string-match-p "\\`; LLVM IR for selection-sort, one copy" text)
+                                 (string-match-p "^;; selection-sort at \\$t = i32$" text)
+                                 (string-match-p "^;; selection-sort at \\$t = f64$" text)
+                                 (string-match-p "^define .*flan\\.selection-sort-i32" text)
+                                 (string-match-p "^define .*flan\\.selection-sort-f64" text)))
+          (test-flan--check "each copy names the file the generic was sent from"
+                            (string-match-p (regexp-quote file) text)))))
+
     (flan-quit)
     (ignore-errors (delete-file socket3)))
 
@@ -1841,6 +1879,30 @@ already rely on it — so nothing here is a stand-in for the real thing."
   ;; anything being shut at all.  `invisible-p' is the predicate that means
   ;; what it says, and it means it whether outline folded with an overlay or
   ;; with a text property.
+  ;;
+  ;; A generic is compiled only as its copies, so its own name finds nothing
+  ;; and each copy is shown under a line naming it.  A function that merely
+  ;; shares the prefix and was written elsewhere is not a copy.
+  (with-temp-buffer
+    (let ((flan--defs
+           '(("sort" "fn" "sort [[$t]] ()" "<prelude>:331:7" "")
+             ("sort-i32" "fn" "sort-i32 [[i32]] ()" "<prelude>:331:7" "")
+             ("sort-f64" "fn" "sort-f64 [[f64]] ()" "<prelude>:331:7" "")
+             ("sort-bytes" "fn" "sort-bytes [[[u8]]] ()" "<prelude>:1595:7" "")))
+          (flan-lower-fetch-function
+           (lambda (section _file name _flags)
+             (unless (equal name "sort") (format "%s of %s\n" section name))))
+          (flan-lower--file "x.flan")
+          (flan-lower--name "sort")
+          (flan-lower--flags nil)
+          (flan-lower--texts nil))
+      (flan-lower--gather '(ir))
+      (let ((text (alist-get 'ir flan-lower--texts)))
+        (test-flan--check "a generic's lowering is each of its copies, named"
+                          (and (string-match-p "^;; sort-f64\nir of sort-f64$" text)
+                               (string-match-p "^;; sort-i32\nir of sort-i32$" text)
+                               (not (string-match-p "sort-bytes" text)))))))
+
   (let* ((flan-lower--state (copy-alist flan-lower--state))
          (flan-lower-fetch-function
           (lambda (section _file name _flags)
diff --git a/lib/check.ml b/lib/check.ml
index ff93f8bb..80b92b58 100644
--- a/lib/check.ml
+++ b/lib/check.ml
@@ -407,6 +407,37 @@ let spell_arg stand_for (a : Ast.expr) =
   | Ast.UInt (_, s) -> s
   | _ -> stand_for
 
+(* Operators other languages spell differently, each mapped to the Flan
+   builtin that computes the same thing. Only exact equivalents: [mod] is left
+   out because Clojure's is floored and [%] is not. *)
+let operator_aliases =
+  [ ("not=", ("!=", "Not-equal")); ("=/=", ("!=", "Not-equal"));
+    ("/=", ("!=", "Not-equal")); ("<>", ("!=", "Not-equal"));
+    ("==", ("=", "Equality")); ("===", ("=", "Equality"));
+    ("&&", ("and", "Logical and")); ("||", ("or", "Logical or"));
+    ("!", ("not", "Logical not")) ]
+
+(* The fix, as the sentence that ends the refusal. The reader's call is
+   written back out under the Flan name only when every argument can be
+   spelled and the count is one the builtin takes, so a suggestion printed as
+   code compiles once pasted. An argument that cannot be spelled leaves the
+   call as it was, with only the name to change; a count the builtin does not
+   take gets the builtin's shape. *)
+let alias_fix flan (args : Ast.expr list) =
+  let spelled = List.map (spell_arg "") args in
+  let n = List.length args in
+  let arity_ok =
+    match flan with
+    | "not" -> n = 1
+    | "and" | "or" -> true
+    | _ -> n >= 2
+  in
+  if not arity_ok then
+    Printf.sprintf "It is called as %s"
+      (if flan = "not" then "(not x)" else "(" ^ flan ^ " x y)")
+  else if List.mem "" spelled then Printf.sprintf "Write %s in its place" flan
+  else Printf.sprintf "Write (%s)" (String.concat " " (flan :: spelled))
+
 (* What a [break] or a [continue] may be talking about, innermost first.
 
    [Lloop] is a loop it is lexically inside, carrying its label if it was given
@@ -1197,6 +1228,21 @@ let rec resolve env ?(seen = []) (t : Ast.texpr) : Types.t =
           [Types.t] and therefore to the layout calculator, both backends,
           [Render] and the DWARF path. docs/SPIKE-GENERICS.md, question 4,
           prices it and leaves it out. *)
+       (* A head that is not a type at all but one edit from one is the typo
+          [(Vect i32)], and the generics sentence would answer a question
+          nobody asked. *)
+       let constructors = [ "Ptr"; "Option"; "Vec"; "Map" ] in
+       (match
+          if Hashtbl.mem env.aliases name || Hashtbl.mem env.structs name
+             || Hashtbl.mem env.datas name || Hashtbl.mem env.unions name
+             || Hashtbl.mem env.enums name
+          then None
+          else near_miss env ~also:constructors name
+        with
+        | Some m when List.mem m constructors ->
+          Loc.failk "check/unknown-type" loc
+            "unknown type %s — did you mean %s?" name m
+        | _ -> ());
        fail loc
          "%s takes no type arguments. A generic function is written with $t \
           in its parameter vector; a generic type is not there yet"
@@ -1396,6 +1442,53 @@ let is_type_name env n =
      slot holding one is a type however few of them there are. *)
   || (n <> "" && n.[0] = '$')
 
+(* A defn written without its return type puts the body's first form in the
+   slot, and [(dotimes [i n] ...)] parses as a type application. Every type
+   application's head is a constructor, and a constructor is capitalised, so a
+   lowercase head there — or the name of a function — is a body form and not a
+   malformed type. A capitalised head that is neither stays with [resolve],
+   whose unknown-type and no-type-arguments sentences are the right ones for
+   [(Vect i32)] and [(Pair i32)]. *)
+let missing_return_type env (fn : Ast.fn) =
+  match fn.Ast.ret with
+  | Some { Ast.t = Ast.Tapp (head, args); tloc } ->
+    let lowercase =
+      head <> "" && not (head.[0] >= 'A' && head.[0] <= 'Z')
+    in
+    let constructor =
+      List.mem head [ "Ptr"; "Option"; "Vec"; "Map"; "Result" ]
+    in
+    (* [(vec i32)] is the constructor with the wrong case, not a body form —
+       but only while every argument is a type, since [(map inc xs)] is a
+       body form whose head is a function. *)
+    let args_are_types =
+      List.for_all
+        (fun (a : Ast.texpr) ->
+           match a.Ast.t with Ast.Tname n -> is_type_name env n | _ -> true)
+        args
+    in
+    (match
+       List.find_opt
+         (fun c -> String.lowercase_ascii c = String.lowercase_ascii head
+                   && c <> head)
+         [ "Ptr"; "Option"; "Vec"; "Map" ]
+     with
+     | Some c when args_are_types && not (is_type_name env head) ->
+       Loc.failk "check/unknown-type" tloc
+         "unknown type %s — did you mean %s?" head c
+     | _ -> ());
+    if (not constructor) && (not (is_type_name env head))
+       && (lowercase || Hashtbl.mem env.fns head
+           || List.mem head !builtin_names)
+    then
+      Loc.failk "check/return-type-missing" tloc
+        "%s has no return type: (%s ...) stands where the return type goes, \
+         and %s is not a type. The return type is written between the \
+         parameter vector and the body, and a function that returns nothing \
+         writes () there"
+        fn.Ast.name head head
+  | _ -> ()
+
 (* Before a bare symbol is allowed to become an unannotated parameter, the two
    ways it is more likely to be a type that went wrong.
 
@@ -9355,6 +9448,15 @@ and ordinary_call ctx ~want loc name args =
           name dname dname c.Tast.vname dname c.Tast.vname
       else if Hashtbl.mem ctx.env.structs name then
         positional_struct ctx ~want loc name args
+      else if List.mem_assoc name operator_aliases then
+        (* Asked before the package test, because [/=] and [=/=] have a slash
+           in them and are not package calls. The did-you-mean cannot reach
+           these: [not=] is one edit from [not], which is the wrong answer,
+           and [&&] is no edit at all from [and]. *)
+        let flan, what = List.assoc name operator_aliases in
+        Loc.failk "check/unknown-function" loc
+          "there is no %s. %s is %s. %s" name what flan
+          (alias_fix flan args)
       else if String.contains name '/' then
         unimplemented loc
           (Printf.sprintf "the call %s into an imported package" name) 4
@@ -10980,6 +11082,7 @@ let collect env (decls : Ast.decl list) =
          let fields = List.map field ms in
          Hashtbl.replace env.unions n { Tast.sname = n; fields }
        | Ast.Defn fn ->
+         missing_return_type env fn;
          (* A signature that introduces a type variable is a *pattern*, not a
             signature: it goes in [gsigs] and the function goes nowhere near
             [fns], because nothing can be called at [t]. Every call site turns
diff --git a/lib/dev.ml b/lib/dev.ml
index dd6c6fbe..dfe19dda 100644
--- a/lib/dev.ml
+++ b/lib/dev.ml
@@ -649,6 +649,59 @@ let host_loc t name =
   | Some f -> Loc.to_string f.Tast.floc
   | None -> ""
 
+(* A generic is never a [Tast.fn]: the checker keeps it as the AST it was
+   written as, and each type it is called at makes an ordinary copy under a
+   name of its own ([selection-sort-i32]). So a by-name op asked for the name
+   that was written finds nothing in the program, and these are how it gets
+   from that name to what the program does hold. *)
+
+(* Its signature as written, [$] and all — [Types.to_string] prints a variable
+   bare, and [[t]] is not how anyone wrote it. *)
+let generic_signature t name =
+  match Hashtbl.find_opt t.session.Session.env.Check.gsigs name with
+  | None -> None
+  | Some (vars, params, ret) ->
+    let dollar = List.map (fun v -> (v, Types.Var ("$" ^ v))) vars in
+    let show ty = Types.to_string (Check.subst_ty dollar ty) in
+    Some
+      (Printf.sprintf "%s [%s] %s" name
+         (String.concat " " (List.map show params)) (show ret))
+
+(* The copies of generic [name] the program holds, each with the types its
+   variables were bound to, spelled [$t = i32]. Read off the program: a copy
+   a [C-x C-e] made is kept in it, and [eval_expr] records the thunk's module
+   as that copy's owner, since no other module defines it. *)
+let generic_copies t name =
+  let env = t.session.Session.env in
+  match Hashtbl.find_opt env.Check.gsigs name with
+  | None -> []
+  | Some (vars, params, ret) ->
+    List.filter_map
+      (fun (f : Tast.fn) ->
+         if f.Tast.fparent <> None then None
+         else
+           match Check.instantiation_origin env f.Tast.name with
+           | Some (g, ps) when String.equal g name ->
+             let subst = ref [] in
+             if List.length ps = List.length params then
+               ignore
+                 (List.for_all2 (Check.bind_ty ~widen:true subst) params ps
+                  && Check.bind_ty subst ret f.Tast.ret);
+             let bound =
+               List.map
+                 (fun v ->
+                    match List.assoc_opt v !subst with
+                    | Some ty -> Printf.sprintf "$%s = %s" v (Types.to_string ty)
+                    | None -> "$" ^ v)
+                 vars
+             in
+             Some (f, String.concat ", " bound)
+           | _ -> None)
+      t.session.Session.program.Tast.fns
+    (* By the types, alphabetically — [f64] before [i32] — so a listing asked
+       for twice is in the same order whatever order the copies were made in. *)
+    |> List.sort (fun (_, a) (_, b) -> String.compare a b)
+
 (* ── Ops ───────────────────────────────────────────────────────────── *)
 
 (* Every reply is a plist with a :status, so an editor can dispatch on one key
@@ -1046,6 +1099,9 @@ let eval_expr t ~code ~origin ~pause =
        the same instantiation would list it as already there. *)
     let held = Session.held t.session in
     let refused msg = Session.restore t.session held; error msg in
+    let had =
+      List.map (fun (f : Tast.fn) -> f.Tast.name) t.session.Session.program.Tast.fns
+    in
     match Session.eval_expr ~origin ~pause t.session code with
     | c ->
       let before = match result t with Some (g, _) -> g | None -> 0L in
@@ -1077,10 +1133,32 @@ let eval_expr t ~code ~origin ~pause =
       let entered_gen = stop_gen t in
       t.n <- t.n + 1;
       let out = Filename.concat t.dir (Printf.sprintf "e%d.so" t.n) in
+      (* A generic called at a new type makes a copy that is defined in this
+         thunk's module and in no other, so this module is where [disassemble]
+         has to look for it — and its IR is kept for the reason [eval] keeps
+         a module's. *)
+      let ll =
+        Filename.concat t.dir (Printf.sprintf "e%d%s" t.n (module_ext c))
+      in
+      write_file ll c.Session.ir;
+      let copies =
+        List.filter_map
+          (fun (f : Tast.fn) ->
+             if List.mem f.Tast.name had then None else Some f.Tast.name)
+          t.session.Session.program.Tast.fns
+      in
       (match build_module c ~debug:t.session.Session.debug ~out with
        | _ ->
          (match deliver t out with
           | "ok" ->
+            if copies <> [] then begin
+              t.gen <- t.gen + 1;
+              List.iter
+                (fun n ->
+                   Hashtbl.replace t.owners n
+                     { ogen = t.gen; oso = out; oll = ll; oloc = fn_loc t n })
+                copies
+            end;
             (* Strictly after the delivery, and that ordering is the whole of
                it: the sleeper is woken to look at a ring, so waking it before
                the module is in one buys an empty poll and a five-second wait.
@@ -1644,10 +1722,27 @@ let defs t =
       (fun (name, sign, doc) -> entry ~name ~kind:"builtin" ~sign ~loc:"" ~doc ())
       Check.builtins
   in
+  (* A generic by the name it was written under. The program holds only its
+     copies, so without these rows the name an author typed was the one name
+     completion, eldoc and [M-.] had never heard of. Kind [fn], because it is
+     one to every reader of this list: it is called, jumped to, and
+     disassembled — the last through [disassemble], which answers a generic's
+     name with its copies. *)
+  let generics =
+    Hashtbl.fold
+      (fun name (g : Ast.fn) acc ->
+         entry ~name ~kind:"fn"
+           ~sign:(Option.value ~default:name (generic_signature t name))
+           ~loc:(Loc.to_string g.Ast.nloc) ()
+         :: acc)
+      t.session.Session.env.Check.generics []
+    |> List.sort compare
+  in
   ok
     [ ":defs "
       ^ Wire.list
-          (fns @ macros @ types @ globals @ externs @ prelude_macros @ builtins)
+          (fns @ generics @ macros @ types @ globals @ externs @ prelude_macros
+           @ builtins)
     ]
 
 (* [(:op "layout" :type T)] — a struct's fields and their types.
@@ -3757,22 +3852,9 @@ let kind_of t name =
   then Some "an extern"
   else None
 
-let disassemble t ~name ~form =
-  if form <> "ir" && form <> "asm" then
-    error
-      (Printf.sprintf
-         "unknown form %S: disassemble takes :form \"ir\" or :form \"asm\"" form)
-  else
-    match find_fn t name with
-    | None ->
-      (match kind_of t name with
-       | Some k ->
-         error
-           (Printf.sprintf
-              "%s is %s, not a function: there is no generated code to show for it"
-              name k)
-       | None -> error (Printf.sprintf "no function named %s in this session" name))
-    | Some f ->
+(* The fields of one function's listing, or why there is none. [name] is the
+   symbol the code was built under, which for a generic's copy is the copy's. *)
+let disassemble_fn t ~name ~form (f : Tast.fn) =
       let o, why = basis t name in
       let common =
         [ ":name " ^ Wire.quote name; ":form " ^ Wire.quote form;
@@ -3793,7 +3875,7 @@ let disassemble t ~name ~form =
          it cannot answer rather than failing at the text of an answer it was
          never going to find. *)
       if form = "ir" && t.session.Session.x86 then
-        error
+        Error
           "this session was compiled by the x86 dev backend, so there is no \
            LLVM IR to show — the listing it produced is assembly. C-c C-a \
            disassembles the object, which works here; for the IR view, restart \
@@ -3803,13 +3885,13 @@ let disassemble t ~name ~form =
         | text ->
           (match ir_of ~ir:text name with
            | Some body ->
-             ok (common @ [ ":object " ^ Wire.quote o.oll; ":text " ^ Wire.quote body ])
+             Ok (common @ [ ":object " ^ Wire.quote o.oll; ":text " ^ Wire.quote body ])
            | None ->
-             error (Printf.sprintf "no define for %s in %s" (Emit.fname name) o.oll))
+             Error (Printf.sprintf "no define for %s in %s" (Emit.fname name) o.oll))
         | exception Sys_error m ->
-          error ("the IR this body was built from is gone: " ^ m)
+          Error ("the IR this body was built from is gone: " ^ m)
       else if not (Sys.file_exists o.oso) then
-        error ("the object this body was linked into is gone: " ^ o.oso)
+        Error ("the object this body was linked into is gone: " ^ o.oso)
       else
         (* The kept source is what the source lines come from: the assembly's
            map on x86, the [.ll]'s headings for an LLVM line table. Missing is
@@ -3837,12 +3919,75 @@ let disassemble t ~name ~form =
                     "source interleaving needs line tables, which an LLVM \
                      session has only when started with flan dev --llvm --debug" ]
           in
-          ok
+          Ok
             (common
              @ [ ":object " ^ Wire.quote o.oso ]
              @ note
              @ [ ":text " ^ Wire.quote text ])
-        | Error m -> error m
+        | Error m -> Error m
+
+(* A generic's name answers with its copies: one is shown as any function is,
+   with [:generic] and [:types] beside it, and several come back as
+   [:copies], a list of those replies, one per type it was called at. *)
+let disassemble t ~name ~form =
+  if form <> "ir" && form <> "asm" then
+    error
+      (Printf.sprintf
+         "unknown form %S: disassemble takes :form \"ir\" or :form \"asm\"" form)
+  else
+    match find_fn t name with
+    | Some f ->
+      (match disassemble_fn t ~name ~form f with
+       | Ok fields -> ok fields
+       | Error m -> error m)
+    | None when Check.is_generic t.session.Session.env name ->
+      let sign = Option.value ~default:name (generic_signature t name) in
+      let copy ((f : Tast.fn), bound) =
+        Result.map
+          (fun fields ->
+             fields
+             @ [ ":generic " ^ Wire.quote name; ":types " ^ Wire.quote bound ])
+          (disassemble_fn t ~name:f.Tast.name ~form f)
+      in
+      (match generic_copies t name with
+       | [] ->
+         error
+           (Printf.sprintf
+              "%s is generic — %s — and nothing in this session calls it \
+               yet, so no code has been made for it. Each type it is called \
+               at gets its own compiled copy: evaluate a function that calls \
+               it, then disassemble %s again"
+              name sign name)
+       | [ c ] ->
+         (match copy c with Ok fields -> ok fields | Error m -> error m)
+       | cs ->
+         (* One copy that cannot be shown is that copy's entry, named with
+            the reason, and not the whole reply: the others still have code
+            to read. *)
+         let entry (((f : Tast.fn), bound) as c) =
+           match copy c with
+           | Ok fields -> Wire.list fields
+           | Error m ->
+             Wire.list
+               [ ":name " ^ Wire.quote f.Tast.name;
+                 ":signature " ^ Wire.quote (signature_of_fn f);
+                 ":loc " ^ Wire.quote (fn_loc t f.Tast.name);
+                 ":generic " ^ Wire.quote name; ":types " ^ Wire.quote bound;
+                 ":refused " ^ Wire.quote m ]
+         in
+         ok
+           [ ":name " ^ Wire.quote name; ":form " ^ Wire.quote form;
+             ":generic " ^ Wire.quote name;
+             ":signature " ^ Wire.quote sign;
+             ":copies " ^ Wire.list (List.map entry cs) ])
+    | None ->
+      (match kind_of t name with
+       | Some k ->
+         error
+           (Printf.sprintf
+              "%s is %s, not a function: there is no generated code to show for it"
+              name k)
+       | None -> error (Printf.sprintf "no function named %s in this session" name))
 
 (* ── The watch table ───────────────────────────────────────────────── *)
 
diff --git a/test/test_dev.ml b/test/test_dev.ml
index 77547f29..14f11ef1 100644
--- a/test/test_dev.ml
+++ b/test/test_dev.ml
@@ -3290,6 +3290,161 @@ let () =
 
     (* ── Disassembly ───────────────────────────────────────────────── *)
 
+    (* A generic is compiled only as its copies, one per type it is called at,
+       so its own name has to be answered with those — the name the author
+       typed is the one the program never holds. Sent from a file that is not
+       the program's, which is how the report came in. Run against a daemon
+       of each backend, with the view each one has. *)
+    let generic_disassembly c ~backend ~form =
+      let said r = Option.value ~default:"" (Wire.string_field r "message") in
+      let file = "/tmp/flan-devtest-sorts.flan" in
+      let eval code =
+        request c
+          (Printf.sprintf "(:op \"eval\" :code %s :file %s)" (Wire.quote code)
+             (Wire.quote file))
+      in
+      let ask () =
+        request c
+          (Printf.sprintf
+             "(:op \"disassemble\" :name \"selection-sort\" :form %S)" form)
+      in
+      let r =
+        eval
+          "(defn selection-sort [xs [$t]] ()\n  {:where (ordered? $t)}\n  \
+           (dotimes [i (length xs)]\n    (let [m i]\n      (dotimes [j \
+           (length xs)]\n        (when (< (at xs j) (at xs m)) (set m j)))\n      \
+           (swap xs i m))))"
+      in
+      if status r <> "ok" then fail "%s: sending a generic: %s" backend (said r)
+      else begin
+        let r = ask () in
+        if status r <> "error" then
+          fail "%s: a generic nothing calls was disassembled" backend
+        else if not (contains_sub (said r) "is generic")
+             || not (contains_sub (said r) "[[$t]]")
+             || not (contains_sub (said r) "evaluate a function that calls it")
+        then fail "%s: a generic nothing calls is refused for the wrong reason: %s"
+               backend (said r);
+        let r = request c "(:op \"defs\")" in
+        (match Wire.field r "defs" with
+         | Some { Form.v = Form.List rows; _ } ->
+           let row =
+             List.find_opt
+               (fun (d : Form.t) ->
+                  match d.Form.v with
+                  | Form.List ({ Form.v = Form.Str "selection-sort"; _ } :: _) ->
+                    true
+                  | _ -> false)
+               rows
+           in
+           (match row with
+            | Some { Form.v = Form.List [ _; { Form.v = Form.Str "fn"; _ };
+                                          { Form.v = Form.Str sign; _ };
+                                          { Form.v = Form.Str loc; _ }; _ ]; _ }
+              ->
+              if sign <> "selection-sort [[$t]] ()" then
+                fail "%s: the generic's signature is not as written: %s" backend sign;
+              if loc <> file ^ ":1:7" then
+                fail "%s: the generic's location is not where it was sent from: %s"
+                  backend loc
+            | _ -> fail "%s: defs does not list the generic by its name" backend)
+         | _ -> fail "%s: defs answered no list" backend);
+        let r =
+          eval
+            "(defn use-sort [] ()\n  (let [a [3 1 2]] (selection-sort (slice a 0 3))))"
+        in
+        if status r <> "ok" then fail "%s: calling the generic at i32: %s" backend (said r)
+        else begin
+          let r = ask () in
+          if status r <> "ok" then
+            fail "%s: the generic with one copy: %s" backend (said r)
+          else begin
+            if Wire.string_field r "name" <> Some "selection-sort-i32" then
+              fail "%s: the one copy is not the one shown" backend;
+            if Wire.string_field r "types" <> Some "$t = i32" then
+              fail "%s: the one copy does not say its types" backend;
+            if Wire.string_field r "loc" <> Some (file ^ ":1:7") then
+              fail "%s: the one copy does not name the file it came from: %s"
+                backend (Option.value ~default:"" (Wire.string_field r "loc"));
+            if not (contains_sub
+                      (Option.value ~default:"" (Wire.string_field r "text"))
+                      (if form = "ir" then "flan.selection-sort-i32" else "ret"))
+            then fail "%s: the one copy's listing is not its code" backend
+          end
+        end;
+        let r =
+          eval
+            "(defn use-sort [] ()\n  (let [a [3 1 2]] (selection-sort (slice a 0 3)))\n  \
+             (let [b [3.0 1.0]] (selection-sort (slice b 0 2))))"
+        in
+        if status r <> "ok" then fail "%s: calling the generic at f64: %s" backend (said r)
+        else begin
+          let r = ask () in
+          if status r <> "ok" then
+            fail "%s: the generic with two copies: %s" backend (said r)
+          else
+            match Wire.field r "copies" with
+            | Some { Form.v = Form.List [ a; b ]; _ } ->
+              let types f =
+                Option.value ~default:"" (Wire.string_field f "types")
+              in
+              if types a <> "$t = f64" || types b <> "$t = i32" then
+                fail "%s: the copies are not headed by their types: %s, %s"
+                  backend (types a) (types b);
+              List.iter
+                (fun f ->
+                   let name = Option.value ~default:"" (Wire.string_field f "name") in
+                   let text = Option.value ~default:"" (Wire.string_field f "text") in
+                   if form = "ir" && not (contains_sub text ("flan." ^ name)) then
+                     fail "%s: the copy %s shows some other code" backend name;
+                   if text = "" then fail "%s: the copy %s has no listing" backend name)
+                [ a; b ]
+            | _ -> fail "%s: two copies did not come back as two" backend
+        end;
+        (* A copy made by an evaluated expression is defined only in that
+           expression's module, which is where its code has to be read from —
+           and the copies made before it are still shown beside it. *)
+        let r =
+          request c
+            "(:op \"eval-expr\" :code \"(selection-sort (slice [(i64 3) (i64 1)] 0 2))\")"
+        in
+        if status r <> "ok" then
+          fail "%s: calling the generic at i64 from an expression: %s" backend (said r)
+        else begin
+          let r = ask () in
+          if status r <> "ok" then
+            fail "%s: the generic with a copy an expression made: %s" backend (said r)
+          else
+            match Wire.field r "copies" with
+            | Some { Form.v = Form.List [ _; _; _ ] as l; _ } ->
+              let l = match l with Form.List l -> l | _ -> [] in
+              List.iter
+                (fun f ->
+                   let name = Option.value ~default:"" (Wire.string_field f "name") in
+                   match Wire.string_field f "refused" with
+                   | Some m -> fail "%s: the copy %s has no listing: %s" backend name m
+                   | None ->
+                     let text = Option.value ~default:"" (Wire.string_field f "text") in
+                     if form = "ir" && not (contains_sub text ("flan." ^ name)) then
+                       fail "%s: the copy %s shows some other code" backend name;
+                     if text = "" then fail "%s: the copy %s has no listing" backend name)
+                l;
+              (match
+                 List.find_opt
+                   (fun f -> Wire.string_field f "types" = Some "$t = i64") l
+               with
+               | Some f ->
+                 (match Wire.string_field f "object" with
+                  | Some o when String.starts_with ~prefix:"e" (Filename.basename o) -> ()
+                  | o ->
+                    fail "%s: the expression's copy is not read from its module: %s"
+                      backend (Option.value ~default:"" o))
+               | None -> fail "%s: the expression's copy is not listed" backend)
+            | _ -> fail "%s: three copies did not come back as three" backend
+        end
+      end
+    in
+
     (* A third daemon, over a program that keeps running, because the two
        claims here are about *which* module owns a name and what the answer is
        allowed to say it means — and both change the moment a body is
@@ -3457,6 +3612,7 @@ let () =
         "\"ir\" or";
       refused "a request with no name" "(:op \"disassemble\" :form \"asm\")"
         "needs :name";
+      generic_disassembly c ~backend:"llvm" ~form:"ir";
 
       (* A stopped program has not thereby failed to install. The commonest way
          to stop is to install a body and have it error, so the one thing the
@@ -3738,6 +3894,7 @@ let () =
             fail "annotate: the delivered wind's positions are not the buffer's:\n%s"
               (text r)
         end;
+        generic_disassembly c ~backend:"x86" ~form:"asm";
         ignore (request c "(:op \"close\")");
         Unix.close c;
         if not
diff --git a/test/test_flan.ml b/test/test_flan.ml
index 323cf3ee..2e265ce7 100644
--- a/test/test_flan.ml
+++ b/test/test_flan.ml
@@ -2446,6 +2446,69 @@ let () =
      reach past anything. Four claims: the call is refused, the refusal says
      what to write instead, the name binds in every position, and a defn under
      it earns no shadowing warning. *)
+  (* ── Operators spelled as other languages spell them ─────────────── *)
+  rejects_check "not= names !="
+    "(defn f [a i32 b i32] bool (not= a b))"
+    ~needle:"there is no not=. Not-equal is !=. Write (!= a b)";
+  accepts "and the call it writes compiles"
+    "(defn f [a i32 b i32] bool (!= a b))";
+  rejects_check "not= over calls says which name to change"
+    "(defn f [a i32 b i32] bool (not= (+ a 1) b))"
+    ~needle:"Write != in its place";
+  rejects_check "/= is not a package call"
+    "(defn f [a i32 b i32] bool (/= a b))" ~needle:"Write (!= a b)";
+  rejects_check "=/= is not a package call"
+    "(defn f [a i32 b i32] bool (=/= a b))" ~needle:"Write (!= a b)";
+  rejects_check "== names ="
+    "(defn f [a i32 b i32] bool (== a b))" ~needle:"Write (= a b)";
+  rejects_check "&& names and"
+    "(defn f [a bool b bool] bool (&& a b))" ~needle:"Write (and a b)";
+  accepts "and that call compiles" "(defn f [a bool b bool] bool (and a b))";
+  rejects_check "|| names or"
+    "(defn f [a bool b bool] bool (|| a b))" ~needle:"Write (or a b)";
+  rejects_check "! names not"
+    "(defn f [a bool] bool (! a))" ~needle:"Write (not a)";
+  rejects_check "a ! at an arity not does not take gets not's shape"
+    "(defn f [a bool b bool] bool (! a b))" ~needle:"called as (not x)";
+  rejects_check "a bare && is written back as the and that compiles"
+    "(defn f [] bool (&&))" ~needle:"Write (and)";
+  accepts "and it does" "(defn f [] bool (and))";
+  accepts "a program's own not= is its own"
+    "(defn not= [a i32 b i32] bool (!= a b)) \
+     (defn f [a i32 b i32] bool (not= a b))";
+
+  (* ── A defn with no return type ───────────────────────────────────
+     The body's first form lands in the return slot and parses as a type
+     application; the refusal names the missing return type rather than the
+     form's head. *)
+  rejects_check "a body form in the return slot is a missing return type"
+    "(defn f [s string] (dotimes [i (length s)] (println i)))"
+    ~needle:"f has no return type: (dotimes ...) stands where the return type goes";
+  rejects_check "and says how a function returning nothing is written"
+    "(defn f [a i32 b i32] (+ a b))"
+    ~needle:"a function that returns nothing writes () there";
+  accepts "the fix compiles"
+    "(defn f [s string] () (dotimes [i (length s)] (println i)))";
+  accepts "a type application in the slot is still a type"
+    "(defn f [] (Option i32) None)";
+  rejects_check "a misspelled constructor is a near miss"
+    "(defn f [] (Optoin i32) None)" ~needle:"unknown type Optoin — did you mean Option?";
+  rejects_check "a lowercase vec is Vec"
+    "(defn f [] (vec i32) (vec-new i32))" ~needle:"unknown type vec — did you mean Vec?";
+  rejects_check "a lowercase ptr is Ptr"
+    "(defn f [p (Ptr i32)] (ptr i32) p)" ~needle:"unknown type ptr — did you mean Ptr?";
+  rejects_check "a lowercase option is Option"
+    "(defn f [] (option i32) None)" ~needle:"unknown type option — did you mean Option?";
+  rejects_check "a lowercase map is Map"
+    "(defn f [] (map i32 i32) (map-new i32 i32))"
+    ~needle:"unknown type map — did you mean Map?";
+  rejects_check "a map over values in the slot is a body form"
+    "(defn f [inc i32 xs i32] (map inc xs))" ~needle:"f has no return type";
+  rejects_check "an unknown capitalised head keeps the generics sentence"
+    "(defn f [] (Pair i32) 0)" ~needle:"Pair takes no type arguments";
+  rejects_check "a misspelled plain return type is still an unknown type"
+    "(defn f [] i3 0)" ~needle:"unknown type i3";
+
   rejects_check "len is not a builtin"
     "(defn f [s [i32]] i32 (len s))" ~needle:"there is no len";
   rejects_check "and the refusal writes the call out"