Hook "WACurrentRequestContext" into debugger?

On Fri, Dec 4, 2015 at 12:05 PM, Max Leske <[hidden email]> wrote:

On 04 Dec 2015, at 14:29, Mariano Martinez Peck <[hidden email]> wrote:

Max...Seaside uses WADynamicVariable (NOT DynamicVariable) which are completely different. WADynamicVariable uses exception mechanism while DynamicVariable uses the ProcessSpecificVariable. 

But thanks anyway!

Oh man…. Sorry :)

I wonder, why WADynamicVariable *isn’t* a DynamicVariable. The semantics are the same if I’m not mistaken (e.g. only available in the current process) and I think access to a dynamic variable may even be faster because it *doesn’t* use the exception mechanism (i.e. no need to walk down the stack). 

If someone knows the answer, I’d be happy to hear it.

I bet it's because of portability. For example, i remember in GemStone the ProcessorLocalVariable did not behave the same as in Pharo. And it was actually an experiment. I think you cannot expect all this stuff to be ansi (or easily portable), while exceptions do. 

 

I’ve played around with Process>>signalException: and Context>>handleSignal: (which looked quite promising) but didn’t get any results. I’m out of ideas.

I have played all morning with an idea of using local variables. I arrive to the point where I DO HAVE the request context at hand, but I don't find an easy way to hook into do-its, print-it etc so that the closure evaluated gets the request context plugged. In other ways... let's say I have the context stored somewhere. I am at the SmalltalkEditor >> evaluateSelectionAndDo: aBlock

and so..somewhere I need to do something like:

WACurrentRequestContext use: self storedContextSomewhere during: [  self theSelectionToBeEvaluated ]

and that's where I am now :)

 

 

Cheers,

Max

On Fri, Dec 4, 2015 at 7:32 AM, Max Leske <[hidden email]> wrote:

Here’s a snippet to play with:

p := Processor activeProcess.

x := 2.

v := TestDynamicVariable value: x during: [  

((p instVarNamed: 'env') ifNotNil: [ :env|

env copyWithout: nil ]) inspect

].

((p instVarNamed: 'env') ifNotNil: [ :env|

env copyWithout: nil ]) inspect

Cheers,

Max

On 04 Dec 2015, at 10:47, Max Leske <[hidden email]> wrote:

I feel you :)

Without having thought this through completely: if you look at the implementation of DynamicVariable>>value:during: you’ll see that the way it works is that the variable is bound to the active process. In the debugger you have access to the process that is being debugged and thus you should have access to the variables bound to it. You could try accessing all such variables by iterating over them (which I think will require an extension on Process because you’d need to access at least the PSKeys class variable).

Cheers,

Max

On 04 Dec 2015, at 00:34, Mariano Martinez Peck <[hidden email]> wrote:

Hi guys,

This thing I will ask in this email it's in my mind since YEARS. But I have always thought it was like that and that there was nothing we could do. However, I think it's time I ask again :)

For those that have used Seaside, and you try to debug, you know that upon request processing seaside uses Exceptions mechanisim to always have access to the request, session, etc. They way that is done is very smart :)

 WACurrentRequestContext use: self during: aBlock

In that case, "self" is the request instance and aBlock the closure that takes care of the request processing. So, inside that closure, everywhere you do "WACurrentRequestContext value" you get the correct request instance.

So..that's great for Seaside, but debugging gets complicated. While you can restart, proceed, etc, once inside debugger, you  cannot evaluate any piece of code that will use the session  or request because you get a WARequestContextNotFound. Of course, because I guess the evaluation you do from cmd+d on a piece of text or via the debugger inspector, creates another closure/context which does not receive the WACurrentRequestContext instance. 

Now....besides WACurrentRequestContext I have my own class UserContextInformation where I basically have a bunch of stuff associated to the logged user. And I do exactly the same as the WACurrentRequestContext. And I have the same problem. I really want to be able to fix this.

Anyone have an idea on how can I do it? I guess I can change the debugger, in the place where I evaluate code so that I wrap that evaluation with my request context instance???

Thoughts?

--

Mariano
http://marianopeck.wordpress.com

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Mariano
http://marianopeck.wordpress.com

--

Mariano
http://marianopeck.wordpress.com