[Vm-dev] Cog: A question about: setInterruptCheckChain()

Torsten Bergmann astares at gmx.de
Fri Oct 1 07:50:45 UTC 2010

Anything I can say on this topic is that it works well
to move more and more stuff moved from the VM to the image
and once you are used to it you will see that writing 
external DLL's/plugins is cumbersome and only required 
in special cases.

Writing a plugin doesnt mean you have more memory security
since it can have a bug too. Also look at the long development 
cycle using C/C++ and the need to set up the tools correctly.

Yes, I know there is Smalltalk/X where you can write C directly
in the method body - but I still think Smalltalk has more power 

And it works well to do most stuff in Smalltalk itself:

Look at Smalltalk/MT - you can easily call API functions
in Smalltalk style:

  WINAPI MessageBox: 0 with: szText with: szTitle with: 0.

Here is an example method and since it is directly in
Smalltalk(MT) it is easily changeable and debuggable:

formatError: uError
	Formats an error string, given the error code.
		uError	A system error code 
	Return Value:
		A String with an error description.
	| count pBuffer answer|
	pBuffer := LONG localNew.
		with: NULL	" ignored "
		with: uError
		with: NULL	" language identifier "
		with: pBuffer basicAddress
		with: 1		" minimum number of characters "
		with: NULL.
	count == 0 ifTrue: [ 
		_DEBUG_USER == TRUE ifTrue: [
			(WINAPI GetLastError) ~= uError ifTrue: [
				^self formatLastError
		^String wsprintf: 'System Error 0x%x' with: uError
	answer := String fromAddress: pBuffer.
	WINAPI LocalFree: pBuffer.

Smalltalk MT also provides the ability to expose a method/block as 
callback to external code - just put it in a special "callback" method

In Smallscript/S# it was even more easier to do since David
Simmons allowed you to mix syntax styles and import libs
into namespaces:


Also see http://double.co.nz/smallscript/unofficialfaq.htm   

With an easy to use FFI/Callback mechanism Smalltalkers would be 
able to integrate more with the platform. I think this is one
of the major problems for acceptance of Smalltalk. Where is 
Squeak's COM binding, interfacing with the window system, ... 

Currently only a few of us really integrate with the outside world
because they know how to write plugins...
It is just to cumbersome how it is today!

I agree with others here: we have the power and tools in Smalltalk
and should move more and more stuff to the image.
Make it run, make it right and then make it fast (and only in the
worst case with a custom plugin written in C).


Neu: GMX De-Mail - Einfach wie E-Mail, sicher wie ein Brief!  
Jetzt De-Mail-Adresse reservieren: http://portal.gmx.net/de/go/demail

More information about the Vm-dev mailing list