From 0636eb3b8d642023419677721d228ad1d90418a3 Mon Sep 17 00:00:00 2001
From: Joseph Ferano <joseph@ferano.io>
Date: Fri, 25 Sep 2026 11:47:11 +0700
Subject: [PATCH] A generic's copy that the file does not make is named in its
 lowering rather than left out

---
 TODO.org            |  9 +++++++++
 emacs/flan-lower.el | 24 +++++++++++++-----------
 lib/dev.ml          |  2 ++
 3 files changed, 24 insertions(+), 11 deletions(-)

diff --git a/TODO.org b/TODO.org
index f61963d2..e71d0d34 100644
--- a/TODO.org
+++ b/TODO.org
@@ -1051,6 +1051,10 @@ 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";
@@ -1900,6 +1904,11 @@ 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 4ca995a5..6562f7d1 100644
--- a/emacs/flan-lower.el
+++ b/emacs/flan-lower.el
@@ -435,17 +435,19 @@ function that happens to share the prefix, `sort-bytes' beside `sort'."
               #'string<)))))
 
 (defun flan-lower--fetch-copies (section name)
-  "SECTION for each copy of generic NAME, each under a line naming it, or nil."
-  (let ((parts
-         (delq nil
-               (mapcar
-                (lambda (c)
-                  (let ((text (funcall flan-lower-fetch-function
-                                       section flan-lower--file c
-                                       flan-lower--flags)))
-                    (and text (format ";; %s\n%s" c text))))
-                (flan-lower--copies name)))))
-    (and parts (mapconcat #'identity parts "\n"))))
+  "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.
diff --git a/lib/dev.ml b/lib/dev.ml
index 68f61af1..bd1ffd21 100644
--- a/lib/dev.ml
+++ b/lib/dev.ml
@@ -686,6 +686,8 @@ let generic_copies t name =
              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 ───────────────────────────────────────────────────────────── *)