XTOUCODE doesn't fail for nonexistent mappings (#1816)

assigns a unique otherwise unallocated Unicode code.  Addresses bug reported in #1814

library/UNICODE

@@ -1,14 +1,12 @@
 (DEFINE-FILE-INFO PACKAGE "INTERLISP" READTABLE "INTERLISP" BASE 10)
 
-
(FILECREATED "27-Mar-2024 23:07:42" {WMEDLEY}<library>UNICODE.;73
 100984 
+
(FILECREATED "26-Aug-2024 16:58:36" {WMEDLEY}<library>UNICODE.;74
 100982 
 
       :EDIT-BY rmk
 
-      :CHANGES-TO (FNS UNICODE-EXTEND-TRANSLATION? INVERT-ALL-UNICODE-MAPPINGS ALL-UNICODE-MAPPINGS 
-                       MERGE-UNICODE-TRANSLATION-TABLES)
-                  (VARS UNICODECOMS)
+      :CHANGES-TO (FNS UNICODE-EXTEND-TRANSLATION?)
 
-      :PREVIOUS-DATE "27-Mar-2024 14:50:54" {WMEDLEY}<library>UNICODE.;72)
+      :PREVIOUS-DATE "27-Mar-2024 23:07:42" {WMEDLEY}<library>UNICODE.;73)
 
 
 (PRETTYCOMPRINT UNICODECOMS)
@@ -661,7 +659,8 @@
                 NEXTCODE])
 
 (UNICODE-EXTEND-TRANSLATION?

-  [LAMBDA (CODE TRANSLATION-TABLE)
                           (* ; "Edited 27-Mar-2024 23:02 by rmk")


+  [LAMBDA (CODE TRANSLATION-TABLE)
                           (* ; "Edited 26-Aug-2024 16:49 by rmk")


+                                                             (* ; "Edited 27-Mar-2024 23:02 by rmk")


                                                              (* ; "Edited  5-Feb-2024 13:48 by rmk")


                                                              (* ; "Edited  3-Feb-2024 12:40 by rmk")

 
@@ -673,11 +672,11 @@
                                   'UNICODE-MAPPINGS.TXT)
                            T UNICODEDIRECTORIES))
          (CL:WHEN FILE
-             (SETQ MAPPING (CL:WITH-OPEN-FILE (STREAM FILE :INPUT)
-                                  (FFILEPOS (CONCAT "[" (LRSH CODE 8)
-                                                   " ")
-                                         STREAM NIL NIL NIL T)
-                                  (READ STREAM)))
+             [SETQ MAPPING (CL:WITH-OPEN-FILE (STREAM FILE :INPUT)
+                                  (CL:WHEN (FFILEPOS (CONCAT "[" (LRSH CODE 8)
+                                                            " ")
+                                                  STREAM NIL NIL NIL T)
+                                         (READ STREAM]
              (CL:WHEN MAPPING
 
                  (* ;; 
@@ -1866,23 +1865,23 @@
 
 (PUTPROPS UNICODE
 FILETYPE
 :TCOMPL)
 (DECLARE%: DONTCOPY
-  (FILEMAP (NIL (4211 18357 (UTF8.OUTCHARFN 4221 . 7019) (UTF8.INCCODEFN 7021 . 12633) (UTF8.PEEKCCODEFN
- 12635 . 17375) (\UTF8.BACKCCODEFN 17377 . 18355)) (18358 22612 (UTF16BE.OUTCHARFN 18368 . 19278) (
-UTF16BE.INCCODEFN 19280 . 20296) (UTF16BE.PEEKCCODEFN 20298 . 21529) (\UTF16BE.BACKCCODEFN 21531 . 
-22610)) (22613 26900 (UTF16LE.OUTCHARFN 22623 . 23630) (UTF16LE.INCCODEFN 23632 . 24648) (
-UTF16LE.PEEKCCODEFN 24650 . 25817) (\UTF16LE.BACKCCODEFN 25819 . 26898)) (26901 29830 (READBOM 26911
- . 28915) (WRITEBOM 28917 . 29828)) (29860 33050 (MAKE-UNICODE-FORMATS 29870 . 33048)) (33147 41529 (
-UNICODE.UNMAPPED 33157 . 35231) (UNICODE-EXTEND-TRANSLATION? 35233 . 37152) (UTF8.BINCODE 37154 . 
-39733) (\UTF8.FETCHCODE 39735 . 41527)) (41530 47051 (UTF8.VALIDATE 41540 . 44137) (
-UTF8-SIZE-FROM-BYTE1 44139 . 44571) (NUTF8-BYTE1-BYTES 44573 . 45310) (NUTF8-CODE-BYTES 45312 . 46369)
- (NUTF8-STRING-BYTES 46371 . 47049)) (48482 48831 (XTOUCODE 48492 . 48660) (UTOXCODE 48662 . 48829)) (
-49774 55820 (READ-UNICODE-MAPPING-FILENAMES 49784 . 52731) (READ-UNICODE-MAPPING 52733 . 55818)) (
-55887 69217 (MAKE-UNICODE-TRANSLATION-TABLES 55897 . 64969) (MERGE-UNICODE-TRANSLATION-TABLES 64971 . 
-66105) (MERGE-UNICODE-TRANSLATION-TABLES1 66107 . 69215)) (69218 76326 (INVERT-ALL-UNICODE-MAPPINGS 
-69228 . 72849) (ALL-UNICODE-MAPPINGS 72851 . 76324)) (77294 89725 (WRITE-UNICODE-MAPPING 77304 . 81054
-) (WRITE-UNICODE-INCLUDED 81056 . 85778) (WRITE-UNICODE-MAPPING-HEADER 85780 . 87028) (
-WRITE-UNICODE-MAPPING-FILENAME 87030 . 88560) (HEXSTRING 88562 . 89723)) (89726 90402 (
-XCCS-UTF8-AFTER-OPEN 89736 . 90400)) (92927 98429 (UTF8HEXSTRING 92937 . 95142) (XTOUSTRING 95144 . 
-98064) (XCCSSTRING 98066 . 98427)) (98430 99318 (UNHEXSTRING 98440 . 99316)) (99319 100829 (SHOWCHARS 
-99329 . 100827)))))
+  (FILEMAP (NIL (4068 18214 (UTF8.OUTCHARFN 4078 . 6876) (UTF8.INCCODEFN 6878 . 12490) (UTF8.PEEKCCODEFN
+ 12492 . 17232) (\UTF8.BACKCCODEFN 17234 . 18212)) (18215 22469 (UTF16BE.OUTCHARFN 18225 . 19135) (
+UTF16BE.INCCODEFN 19137 . 20153) (UTF16BE.PEEKCCODEFN 20155 . 21386) (\UTF16BE.BACKCCODEFN 21388 . 
+22467)) (22470 26757 (UTF16LE.OUTCHARFN 22480 . 23487) (UTF16LE.INCCODEFN 23489 . 24505) (
+UTF16LE.PEEKCCODEFN 24507 . 25674) (\UTF16LE.BACKCCODEFN 25676 . 26755)) (26758 29687 (READBOM 26768
+ . 28772) (WRITEBOM 28774 . 29685)) (29717 32907 (MAKE-UNICODE-FORMATS 29727 . 32905)) (33004 41527 (
+UNICODE.UNMAPPED 33014 . 35088) (UNICODE-EXTEND-TRANSLATION? 35090 . 37150) (UTF8.BINCODE 37152 . 
+39731) (\UTF8.FETCHCODE 39733 . 41525)) (41528 47049 (UTF8.VALIDATE 41538 . 44135) (
+UTF8-SIZE-FROM-BYTE1 44137 . 44569) (NUTF8-BYTE1-BYTES 44571 . 45308) (NUTF8-CODE-BYTES 45310 . 46367)
+ (NUTF8-STRING-BYTES 46369 . 47047)) (48480 48829 (XTOUCODE 48490 . 48658) (UTOXCODE 48660 . 48827)) (
+49772 55818 (READ-UNICODE-MAPPING-FILENAMES 49782 . 52729) (READ-UNICODE-MAPPING 52731 . 55816)) (
+55885 69215 (MAKE-UNICODE-TRANSLATION-TABLES 55895 . 64967) (MERGE-UNICODE-TRANSLATION-TABLES 64969 . 
+66103) (MERGE-UNICODE-TRANSLATION-TABLES1 66105 . 69213)) (69216 76324 (INVERT-ALL-UNICODE-MAPPINGS 
+69226 . 72847) (ALL-UNICODE-MAPPINGS 72849 . 76322)) (77292 89723 (WRITE-UNICODE-MAPPING 77302 . 81052
+) (WRITE-UNICODE-INCLUDED 81054 . 85776) (WRITE-UNICODE-MAPPING-HEADER 85778 . 87026) (
+WRITE-UNICODE-MAPPING-FILENAME 87028 . 88558) (HEXSTRING 88560 . 89721)) (89724 90400 (
+XCCS-UTF8-AFTER-OPEN 89734 . 90398)) (92925 98427 (UTF8HEXSTRING 92935 . 95140) (XTOUSTRING 95142 . 
+98062) (XCCSSTRING 98064 . 98425)) (98428 99316 (UNHEXSTRING 98438 . 99314)) (99317 100827 (SHOWCHARS 
+99327 . 100825)))))
 STOP