`ARG NOT SELPIECES` error when pressing `F4` in TEdit

[pamoroso]

Describe the bug

When I press the F4 function key in the TEdit window I get a break window with the error:

INTERLISP-ERROR
In ERROR:
ARG NOT SELPIECES
NIL

To Reproduce

Steps to reproduce the behavior:

1. launch Medley
2. launch TEdit
3. with the focus on the TEdit window, press the F4 function key

Expected behavior

No error is reported.

Screenshots

The break window:

The full desktop:

Context (please complete the following information):

• Are you using online.interlisp.org? no
• OS: Linux
• OS Version: Mint 22 Cinnamon
• Display/window system: X11
• Host arch: x86_64 (System76 Merkaat)
• Maiko version: 4994982/master (Medley 90fdbf7/rmk76--TEDIT--new-architecture-for-function-key-bindings+initial-regions)
• IL:MAKESYSDATE: 19-Mar-2025 03:47:59

Additional context

A backtrace:

TEdit/5(debug)BTV
   MESS1 "ARG NOT SELPIECES"
   MESS2 NIL
   NOBREAK NIL
ERROR
\LISPERROR
\DTEST.UFN
   INSERTSELPIECES NIL
   TEXTOBJ {TEXTOBJ}#122,35600
   SEL {SEL: 1-0-L _ 100/35634}
\TEDIT.REPLACE.SELPIECES
   TSTREAM #<IO Text Stream/130,6500>
   CHARFN U-CASECODE
   TEXTOBJ {TEXTOBJ}#122,35600
   SEL {SEL: 1-0-L _ 100/35634}
\TEDIT.KEY.TRANSFORM
   *FORM* (\TEDIT.KEY.TRANSFORM TSTREAM (FUNCTION 
U-CASECODE))
   *ARGVAL* NIL
   *TAIL* NIL
   *FN* \TEDIT.KEY.TRANSFORM
\EVALFORM
   \INTERNAL NIL
EVAL
   SI::*DUMMY-FOR-CATCH* T
   SI::*CATCH-RETURN-FROM* (&)
   CHARCODE 580
   TCH NIL
   FN (\TEDIT.KEY.TRANSFORM TSTREAM (FUNCTION U-CASECODE
))
\TEDIT.COMMAND.LOOPA0001A0002
   SI::*CLEANUP-FORMS* SI::RESETUNWIND
   SI::NLSETQ-VALUE NIL
   *PROCEED-CASES* (&)
   SI::*NLSETQFLAG* NIL
SI::*UNWIND-PROTECT*
   TSTREAM #<IO Text Stream/130,6500>
   TEXTOBJ {TEXTOBJ}#122,35600
   LISPXHIST NIL
   SI::*RESETFORMS* ((&))
   RESETSTATE NIL
\TEDIT.COMMAND.LOOP
   TSTREAM #<IO Text Stream/130,6500>
   WINDOW {WINDOW}#122,31664
   UNSPAWNED NIL
   TEXTOBJ {TEXTOBJ}#122,35600
\TEDIT1
   *FORM* (\TEDIT1 (QUOTE #<IO Text Stream/130,6500>) {
WINDOW}#122,31664 NIL)
   *ARGVAL* NIL
   *TAIL* NIL
   *FN* \TEDIT1
\EVALFORM
   %#FORM# (\TEDIT1 (QUOTE #<IO Text Stream/130,6500>) {
WINDOW}#122,31664 NIL)
   *CURRENT-PROCESS* #<Process TEdit/174,24000>
   HELPFLAG BREAK!
   \CURRENTDISPLAYLINE 0
   \#DISPLAYLINES 15
   \LINEBUF.OFD #<IO Linebuffer Stream/146,12600>
   *READTABLE* #<ReadTable INTERLISP/174,71714>
   \PRIMTERMTABLE {TERMTABLEP}#174,64740
   \PRIMTERMSA {CHARTABLE}#174,65000
   TtyDisplayStream #<Output Display Stream/130,16000>
   SI::*RESETFORMS* NIL
   \INTERRUPTABLE T
   \TTYWINDOW NIL
   READBUF NIL
   \TERM.OFD #<Output Display Stream/146,12300>
   *STANDARD-OUTPUT* #<Output Display Stream/146,12300>
   *STANDARD-INPUT* #<IO Linebuffer Stream/146,12600>
\MAKE.PROCESS0
T

The issue happens also on Medley Online 17-Mar-2025 12:35:46.

[rmkaplan]

Should be fixes in #2070

[pamoroso]

I confirm d4f921a fixes #2075.