On 8 Sep 2004, at 03:17, Richard Gaskin wrote:
Some time ago Dave Cragg wrote:
>> The version of libUrl (1.1a3) currently being distributed with >> the Rev 2.5 beta (engine 2.6.1) is not backwards compatible with >> earlier engines. This is because of syntax added to support >> secure sockets in https URLs.
Can older versions of libURL be used with newer engines (without support for new features, of course)?
Yes.
I'd propose that we do with libURL what we did with the Standalone Builder: have two versions included in the IDE, and use the version appropriate to the engine being used in that session.
Can anyone think of a downside to that?
For the sake of simplicity I like being able to use one IDE build across all versions of the engine from the time the IDE went open source going forward. There may be a time when that goal is no longer supportable, but as long as it is I think it's worth doing.
Any downsides to the approach for libURL proposed here?
I guess there will be a naming issue with the stack. (start using <???>)
The other issue I'm not so sure about is the potential syntax error when using the newer libUrl with an older engine. (The problem syntax is "open secure socket ...") I'm not sure exactly when/if the engine tries to compile loaded stacks. If compiling is only done when a stack is actually called (e.g. after a "start using") then it may be OK. But if all substacks in memory are subject to script compilation, then there may be a problem. (I guess I could check this out. :))
A thought. (Apologies if this is what you had in mind.) One approach might be to make the libUrl stack simply a "loader" stack, with a single "libraryStack" handler. The two "functional" versions of libUrl would be held in custom properties. The libraryStack handler would unpackage the appropriate custom property and start using that stack. I just checked if this is feasible, and it seems to be. Although it seems you can't use "start using" directly on a custom property, you can "go" to a custom property. So something like this might work:
on libraryStack
if "libUrl_" is not in the stacksInUse then
if versionLessThan("2.6.1") then
go invisible stack (the cLibUrl1_0_15 of me) ##contains stack "libUrl_1_0_15"
start using "libUrl_1_0_15"
close stack "libUrl_1_0_15"
else
go invisible stack (the cLibUrl1_1 of me)
start using "libUrl_1_1"
close stack "libUrl_1_1"
end if
end if
end libraryStack
function versionLessThan pTarget
put the version into tCurV
set the itemDel to "."
put 0 into tCount
repeat for each item tNum in pTarget
add 1 to tCount
if item tCount of tCurV < tNum then return true
end repeat
return false
end versionLessThanA problem here might be the size of the libUrl stack that has to be carried around, but I guess the custom properties could be compressed.
Too complicated??
By the way, I just noticed that the libUrl pages on the new Rev website are incomplete (no links to documentation or downloads). I'll check with RunRev what they plan for this. However, it may be a good idea to have the latest updaters posted elsewhere. On the Yahoo site perhaps, along with the IDE. Or should I put together a separate download site? (or both?).
Cheers Dave
_______________________________________________ metacard mailing list [EMAIL PROTECTED] http://lists.runrev.com/mailman/listinfo/metacard
