DINFO: recreate textstream if it has disappeared from the window (#1659)

Not sure how this can happen--a Tedit window without a textstream--but now testing for it.  DINFO must have removed it for some unknown reason.

lispusers/DINFO

@@ -1,12 +1,12 @@
 (DEFINE-FILE-INFO PACKAGE "INTERLISP" READTABLE "INTERLISP" BASE 10)
 
-
(FILECREATED "10-Mar-2024 15:38:36" {WMEDLEY}<lispusers>DINFO.;12
 65343  
+
(FILECREATED "11-Apr-2024 08:27:34" {WMEDLEY}<lispusers>DINFO.;13
 65523  
 
       :EDIT-BY rmk
 
       :CHANGES-TO (FNS DINFO.OPENTEXTSTREAM)
 
-      :PREVIOUS-DATE " 9-Mar-2024 22:21:42" {WMEDLEY}<lispusers>DINFO.;10)
+      :PREVIOUS-DATE "10-Mar-2024 15:38:36" {WMEDLEY}<lispusers>DINFO.;12)
 
 
 (PRETTYCOMPRINT DINFOCOMS)
@@ -1036,18 +1036,20 @@
                 (PROMPTPRINT "DInfo is busy"])
 
 (DINFO.OPENTEXTSTREAM

-  [LAMBDA (FILE WINDOW FROM TO PROPS)
                        (* ; "Edited 10-Mar-2024 15:37 by rmk")

+  [LAMBDA (FILE WINDOW FROM TO PROPS)
                        (* ; "Edited 10-Apr-2024 23:46 by rmk")


+                                                             (* ; "Edited 10-Mar-2024 15:37 by rmk")

                                                              (* drc%: "25-Jan-86 18:24")

     (RESETFORM (TTYDISPLAYSTREAM (GETPROMPTWINDOW WINDOW))
            (LET ((TEXTSTREAM (WINDOWPROP WINDOW 'TEXTSTREAM))
                  (THIS.TEXT (LIST FILE FROM TO)))
-                (if
 (AND (EQUAL THIS.TEXT (fetch
 (DINFOGRAPH
 LAST.TEXT) of
 (DINFOGRAPH
 WINDOW)))
+                (if
 (AND TEXTSTREAM (EQUAL THIS.TEXT (fetch
 (DINFOGRAPH
 LAST.TEXT)
+                                                        of
 (DINFOGRAPH
 WINDOW)))
                          (\GETSTREAM TEXTSTREAM 'INPUT T))
                     then
 
                          (* ;; "Same text, and it's still there and open, so do nothing.")

 
                          TEXTSTREAM
-                  else
 (AND TEXTSTREAM (TEDIT.KILL TEXTSTREAM))
+                  else
 (CL:WHEN TEXTSTREAM (TEDIT.KILL TEXTSTREAM))
                        (CLEARW T)
                        (CLEARW WINDOW)
                        [RESETSAVE NIL `(AND RESETSTATE (WINDOWPROP ,WINDOW 'LAST.TEXT NIL]
@@ -1122,7 +1124,7 @@ DINFO.UPDATE.FROM.MENU 44874 . 45173) (DINFO.UPDATE.HISTORY 45175 . 47705) (DINF
 47707 . 48534)) (48537 58866 (DINFO.UPDATE.GRAPH.DISPLAY 48547 . 49999) (DINFO.UPDATE.FROM.GRAPH 50001
  . 50477) (DINFO.GET.GRAPH.WINDOW 50479 . 51064) (DINFO.CREATE.GRAPH.WINDOW 51066 . 52183) (
 DINFO.SHOWGRAPH 52185 . 53910) (DINFO.INVERT.NODE 53912 . 55300) (DINFO.LAYOUTGRAPH 55302 . 58864)) (
-58867 64756 (DINFO.UPDATE.TEXT.DISPLAY 58877 . 60825) (DINFO.TITLEMENUFN 60827 . 61952) (
-DINFO.OPENTEXTSTREAM 61954 . 63116) (DINFO.SHOWSEL 63118 . 63851) (DINFO.GET.FILENAME 63853 . 64754)))
+58867 64936 (DINFO.UPDATE.TEXT.DISPLAY 58877 . 60825) (DINFO.TITLEMENUFN 60827 . 61952) (
+DINFO.OPENTEXTSTREAM 61954 . 63296) (DINFO.SHOWSEL 63298 . 64031) (DINFO.GET.FILENAME 64033 . 64934)))
 ))
 STOP