--- a/AbstractOperatingSystem.st	Thu Jan 19 11:46:00 2012 +0000
+++ b/AbstractOperatingSystem.st	Sun Jan 22 23:07:15 2012 +0000
@@ -1824,9 +1824,11 @@
      OperatingSystem canExecuteCommand:'cvs'
      OperatingSystem canExecuteCommand:'diff'
      OperatingSystem canExecuteCommand:'cvs.exe'
-    "
-
-    "Created: 4.11.1995 / 19:13:54 / cg"
+     OperatingSystem canExecuteCommand:'hg' 
+     OperatingSystem pathOfCommand:'hg'  
+    "
+
+    "Created: / 04-11-1995 / 19:13:54 / cg"
 !
 
 commandAndArgsForOSCommand:aCommandString
@@ -1872,11 +1874,17 @@
      Usually, '.../stx' is returned -
      but may be different for standAlone apps (or winstx.exe)."
 
-    ^ self pathOfCommand:(self nameOfSTXExecutable)
+    |path|
+
+    path := self pathOfCommand:(self nameOfSTXExecutable).
+    self assert:(path notNil).
+    ^ path
 
     "
      OperatingSystem pathOfSTXExecutable
     "
+
+    "Modified: / 20-01-2012 / 12:52:46 / cg"
 ! !
 
 !AbstractOperatingSystem class methodsFor:'executing OS commands-wrappers'!
@@ -7096,15 +7104,15 @@
 !AbstractOperatingSystem class methodsFor:'documentation'!
 
 version
-    ^ '$Header: /cvs/stx/stx/libbasic/AbstractOperatingSystem.st,v 1.217 2012/01/05 14:29:48 cg Exp $'
+    ^ '$Header: /cvs/stx/stx/libbasic/AbstractOperatingSystem.st,v 1.219 2012/01/20 12:33:14 cg Exp $'
 !
 
 version_CVS
-    ^ 'Header: /cvs/stx/stx/libbasic/AbstractOperatingSystem.st,v 1.217 2012/01/05 14:29:48 cg Exp '
+    ^ 'Header: /cvs/stx/stx/libbasic/AbstractOperatingSystem.st,v 1.219 2012/01/20 12:33:14 cg Exp '
 !
 
 version_SVN
-    ^ '$Id: AbstractOperatingSystem.st 10761 2012-01-19 11:46:00Z vranyj1 $'
+    ^ '$Id: AbstractOperatingSystem.st 10763 2012-01-22 23:07:15Z vranyj1 $'
 ! !
 
 AbstractOperatingSystem initialize!
@@ -7112,3 +7120,4 @@
 
 
 
+