From dfd67aed3c8d2f587a4902e8e1a101d96a01948a Mon Sep 17 00:00:00 2001
From: "Kartik K. Agaram" <vc@akkartik.com>
Date: Mon, 25 Apr 2022 22:10:20 -0700
Subject: [PATCH] copy how Lua 5.3 REPL prints expr values

---
 mu.lua | 31 +++++++++++++++++++++----------
 1 file changed, 21 insertions(+), 10 deletions(-)

diff --git a/mu.lua b/mu.lua
index 8917476..e0342fb 100644
--- a/mu.lua
+++ b/mu.lua
@@ -5,9 +5,6 @@ curses.echo(false) -- unclear why implicit echo can't handle newlines, regardles
 stdscr:clear()
 stdscr:scrollok(true)
 
--- unclear how Lua (post 5.2) is able to selectively print values of variables
--- at the repl
-
 local function gather_results(success, ...)
   local n = select('#', ...)
   return success, { n = n, ... }
@@ -34,7 +31,7 @@ while true do
     stdscr:addstr('>> ')
   end
   buf = buf .. readline()
-  local f, err = load(buf, 'REPL')
+  local f, err = load('return '..buf, 'REPL')
   if f then
     buf = ''
     new_expr = true
@@ -47,14 +44,28 @@ while true do
       print(results[1])
     end
   else
-    stdscr:addstr(err..'\n')
-    if string.match(err, "'<eof>'$") or string.match(err, "<eof>$") then
-      buf = buf .. '\n'
-      new_expr = false
-    else
-      print(err)
+    local f, err = load(buf, 'REPL')
+    if f then
       buf = ''
       new_expr = true
+      local success, results = gather_results(xpcall(f, function(...) return debug.traceback() end))
+      if success then
+        for _, result in ipairs(results) do
+          print(result)
+        end
+      else
+        print(results[1])
+      end
+    else
+      stdscr:addstr(err..'\n')
+      if string.match(err, "'<eof>'$") or string.match(err, "<eof>$") then
+        buf = buf .. '\n'
+        new_expr = false
+      else
+        print(err)
+        buf = ''
+        new_expr = true
+      end
     end
   end
 end