Fix unlikely but possible race in `WeakValueDictionary`
It may happen that value in `valueArray` could have been already
collected by the GC but #clearDeadSlots have not yet been called.
When this happened, `#at:ifAbsentPut:` returned tombstone rather
than updating the dictionary with value from block.
This commit fixes this by checking whether `valueArray` contain
the tombstone and if so, clearing up the dead slots and restarting
the operation. HTH.
"
COPYRIGHT (c) 1993 by Claus Gittinger
All Rights Reserved
This software is furnished under a license and may be used
only in accordance with the terms of that license and with the
inclusion of the above copyright notice. This software may not
be provided or otherwise made available to, or used by, any
other person. No title to or ownership of the software is
hereby transferred.
"
"{ Package: 'stx:libbasic' }"
"{ NameSpace: Smalltalk }"
GenericException subclass:#Exception
instanceVariableNames:''
classVariableNames:''
poolDictionaries:''
category:'Kernel-Exceptions'
!
!Exception class methodsFor:'documentation'!
copyright
"
COPYRIGHT (c) 1993 by Claus Gittinger
All Rights Reserved
This software is furnished under a license and may be used
only in accordance with the terms of that license and with the
inclusion of the above copyright notice. This software may not
be provided or otherwise made available to, or used by, any
other person. No title to or ownership of the software is
hereby transferred.
"
!
documentation
"
Exception is an abstract superclass of all exceptions in the system,
which are not generated by user actions (e.g. keyboard interrupts) nor by
errors in the exception system itself.
Think twice before subclassing directly from Exception. Consider to subclass
from one of Exceptions subclasses Error, Warning, UserNotification...
You should also handle Error instead of Exception, since breakpoints,
halts and user informational messages are processed as exceptions.
The behavior is in GenericException, to allow for some exceptions
(UnhandledExceptionException and UserInterrupts) not to be a child of Exception.
[see also:]
Error
Warning
UserNotification
Notification
Signal
"
! !
!Exception class methodsFor:'testing'!
isAbstract
^ self == Exception
! !
!Exception class methodsFor:'documentation'!
version
^ '$Header$'
!
version_SVN
^ '$Id: Exception.st 10761 2012-01-19 11:46:00Z vranyj1 $'
! !