--- a/extensions.st	Fri May 22 23:03:41 2020 +0100
+++ b/extensions.st	Wed May 27 15:47:18 2020 +0100
@@ -13,11 +13,48 @@
 
 dbgVariables
     "Return a list of variables for this context (as collection 
-     of `DIVariable` instances)"    
+     of `DIVariable` instances) or nil if no debug info is recorded"
 
-    ^ self dbgVariableTable variables select:[:e | e physicalBlockSourceOffset == sourcePos ]
+    | vartab |
+
+    vartab := self dbgVariableTable.
+    ^ vartab notNil ifTrue:[ vartab variables select:[:e | e physicalBlockSourceOffset == sourcePos ] ] ifFalse:[ nil ]
 
     "Created: / 07-02-2019 / 08:46:42 / Jan Vrany <jan.vrany@fit.cvut.cz>"
+    "Modified: / 27-05-2020 / 15:21:57 / Jan Vrany <jan.vrany@labware.com>"
+! !
+
+!Context methodsFor:'special accessing'!
+
+argAndVarNames
+    "helper: given a context, return a collection of arg&var names"
+    "/ 
+    "/ Note that this method overrides the default implementation
+    "/ from stx:libbasic.
+    "/ The default is horrible, complex and buggy, never worked properly.
+    "/ And will be removed later without notice
+
+    |varinfos varnames |
+
+    varinfos := self dbgVariables.
+    varnames := Array new: self numArgs + self numVars.
+    varinfos size ~~ varnames size ifTrue:[ 
+        "/ Not all variables recorded, generate synthetic ones
+        self breakPoint: #jv.  
+        1 to: self numArgs do:[:i | 
+            varnames at: i put: ('arg', i printString)
+        ].
+        self numArgs + 1 to: varnames size do:[:i |
+            varnames at: i put: ('local', (i - self numArgs) printString)
+        ]
+    ].
+    varinfos do:[:varinfo | 
+        varnames at: varinfo frameOffset put: varinfo name
+    ].
+    ^ varnames.
+
+    "Modified: / 26-12-2015 / 08:20:03 / Jan Vrany <jan.vrany@fit.cvut.cz>"
+    "Modified: / 27-05-2020 / 15:40:39 / Jan Vrany <jan.vrany@labware.com>"
 ! !
 
 !Context methodsFor:'accessing'!
@@ -33,10 +70,12 @@
 
 dbgVariables
     "Return a list of variables for this context (as collection 
-     of `DIVariable` instances)"
+     of `DIVariable` instances) or nil if no debug info is recorded"         
+
     ^ method dbgVariables
 
     "Created: / 07-02-2019 / 08:45:28 / Jan Vrany <jan.vrany@fit.cvut.cz>"
+    "Modified (comment): / 27-05-2020 / 15:22:32 / Jan Vrany <jan.vrany@labware.com>"
 ! !
 
 !Method methodsFor:'accessing'!
@@ -61,22 +100,30 @@
 !Method methodsFor:'accessing'!
 
 dbgVariableTable
-    "Return a DIVariableTable for this method"
-    ^ self dbgInfo dbgVariableTable
+    "Return a DIVariableTable for this method or nil if not debug info is recorded"
+    | info |
+
+    info := self dbgInfo.
+    ^ info notNil ifTrue:[ info dbgVariableTable ] ifFalse:[ nil ]
 
     "Created: / 15-07-2018 / 11:52:44 / Jan Vrany <jan.vrany@fit.cvut.cz>"
     "Modified (comment): / 07-02-2019 / 08:41:02 / Jan Vrany <jan.vrany@fit.cvut.cz>"
+    "Modified: / 27-05-2020 / 15:19:45 / Jan Vrany <jan.vrany@labware.com>"
 ! !
 
 !Method methodsFor:'accessing'!
 
 dbgVariables
     "Return a list of variables for this context (as collection 
-     of `DIVariable` instances)"    
+     of `DIVariable` instances) or nil if no debug info is recorded"
 
-    ^ self dbgVariableTable variables select:[:e | e physicalBlockSourceOffset == 0 ]
+    | vartab |
+
+    vartab := self dbgVariableTable.
+    ^ vartab notNil ifTrue:[ vartab variables select:[:e | e physicalBlockSourceOffset == 0 ] ] ifFalse:[ nil ]
 
     "Created: / 07-02-2019 / 08:47:35 / Jan Vrany <jan.vrany@fit.cvut.cz>"
+    "Modified: / 27-05-2020 / 15:21:14 / Jan Vrany <jan.vrany@labware.com>"
 ! !
 
 !Object methodsFor:'user interaction & notifications'!

--- a/stx_libcomp.st	Fri May 22 23:03:41 2020 +0100
+++ b/stx_libcomp.st	Wed May 27 15:47:18 2020 +0100
@@ -1,6 +1,7 @@
 "
  COPYRIGHT (c) 1989 by Claus Gittinger / eXept Software AG
  COPYRIGHT (c) 2016 Jan Vrany
+ COPYRIGHT (c) 2020 LabWare
               All Rights Reserved
 
  This software is furnished under a license and may be used
@@ -27,6 +28,7 @@
 "
  COPYRIGHT (c) 1989 by Claus Gittinger / eXept Software AG
  COPYRIGHT (c) 2016 Jan Vrany
+ COPYRIGHT (c) 2020 LabWare
               All Rights Reserved
 
  This software is furnished under a license and may be used
@@ -262,6 +264,7 @@
         Context dbgVariableTable
         Context dbgVariables
         Method dbgVariables
+        Context argAndVarNames
     )
 !