Inspector goes into infinite loop

#1 08-01-2008, 12:28 AM

I have meet this bug when I demonstrated Smalltalk agile magic to my
numb C++ programmer friends ;-)

So, in the fresh Comminity Edition image try to Ctrl-D this in
Workspace:
Object allInstances.
You'll see something like this: #(an Object an Object an Object an
Object an Object an Object). If you try to inspect this array you will
inspect an infinite loop of the Inspector

Second object of this array causes this behavior.
I.e. Object allInstances second <Ctrl-I> will crash Inspector too.

This object used in RetryCookie class variable in the
ExceptionHandlerAbstract class.

Other Objects instances inspects successfully. I thing this is a bug
of the Inspector.

#2 08-01-2008, 08:55 AM

alex_wh@mail.ru wrote:

> This object used in RetryCookie class variable in the
> ExceptionHandlerAbstract class.
>
> Other Objects instances inspects successfully. I thing this is a bug
> of the Inspector.

I wouldn't call it a bug in the inspector. For example, try the
following (evaluate in ExceptionHandlerAbstract class):
[RetryCookie] on: Error do: [:ex | ]
You'll get an infinite loop without the inspector. The problem is that
the exception handling code uses the RetryCookie object to determine if
it should retry evaluating the block. For example, if you have code like:
| i |
i := 0.
[10 / i] on: Error do: [:ex | i := i + 1. ex retry]
When the #retry is executed, it returns the RetryCookie back to the
exception handler so that the exception handler knows to retry the [10 /
i] block again. Therefore, if you return the RetryCookie as the value of
the block, you'll cause the exception handler to keep retrying the block.

John Brant

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