Makes sense - and having the same libraries loaded will certainly reduce any confusion... can you just have sys.path be empty or different for the 2ndary hosted engines? Also if you're using the pre-compiled modules you could actually just remove the compiled loader from sys.meta_path.
-----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Michael Foord Sent: Friday, October 31, 2008 9:53 AM To: Discussion of IronPython Subject: Re: [IronPython] IronPython 2: Oddity with Hosting API from within IronPython Dino Viehland wrote: > If you also have those modules living on disk in sys.path - yes. But > honestly it is a little scary that you're using modules across > ScriptRuntime's and I can't say that I'd advise that as a best practice. Of > course I don't know that anything will go wrong either but it might get > really confusing... > The basic scenario is that our spreadsheets use a host of our spreadsheet model libraries. If every new document has to import these from scratch then it drastically increases the time (and memory use) associated with creating a new document and doing the first calculation. Of course if importing large amounts of Python code was quicker and used less memory it wouldn't be such an issue. ;-) If a single runtime could have multiple Python engines associated then we could do that, but as far as I can tell creating a new engine from a runtime with an existing engine will always return the existing engine? Though as they are all using the same libraries it seems sensible for them to be shared rather than each document holding an identical copy. If at some point we move to isolate documents using AppDomains then this will obviously change - but the time cost of a new document having to import everything from scratch is a factor in being able to do that. Michael > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Michael Foord > Sent: Friday, October 31, 2008 9:40 AM > To: Discussion of IronPython > Subject: Re: [IronPython] IronPython 2: Oddity with Hosting API from within > IronPython > > Dino Viehland wrote: > >> We try to import from the file system before we attempt to import from the >> DLR (which includes both globals & .NET namespaces). So in this case we'll >> pick up foobar from disk because presumably these 2 engines both share the >> entry in sys.path where foobar lives. >> >> I think long term this logic is going to move into an importer hook because >> by CPython 3.1 the import logic may be written entirely in Python. In that >> case you'd have the ability to re-order the import hooks so you could >> control the precedence. But for now I think it's by design - we don't want >> to block potentially valid imports that would work in CPython (e.g. import >> System :) ). >> >> > > So if we want to pre-populate an engine with modules we *ought* to be > hooking directly into 'sys.modules' of the hosted engines rather than > using runtime.Globals ? > > Michael > > >> -----Original Message----- >> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Michael Foord >> Sent: Friday, October 31, 2008 6:54 AM >> To: Discussion of IronPython >> Subject: [IronPython] IronPython 2: Oddity with Hosting API from within >> IronPython >> >> Hello guys, >> >> In Resolver One we use the IronPython hosting API from inside IronPython >> code. I've noticed an oddity that is not how I would expect the hosting >> API to behave if I was using it from C#. >> >> My understanding is that the correct way to publish a module (make it >> available for a ScriptEngine to import) is to set it in >> 'engine.Runtime.Globals'. >> >> If I do this from within IronPython code with a module I have already >> imported and then execute an import statement in the engine, the module >> is re-imported (code executed) rather than using the one I have >> published to the runtime globals. >> >> If I have a 'foobar' module that prints when importing, the following >> code prints twice instead of the once I would expect: >> >> import sys >> import clr >> clr.AddReference('IronPython') >> clr.AddReference('Microsoft.Scripting') >> >> from IronPython.Hosting import Python >> from Microsoft.Scripting import SourceCodeKind >> >> import foobar >> >> engine = Python.CreateEngine() >> engine.Runtime.Globals.SetVariable('foobar', sys.modules['foobar']) >> >> source = engine.CreateScriptSourceFromString('import foobar\r\n', >> SourceCodeKind.Statements) >> scope = engine.CreateScope() >> source.Compile().Execute(scope) >> >> >> *However*, if I change the code to not use Runtime.Globals, but instead >> do the following, then the module is only imported once and I get one >> print as expected: >> >> hostedSys = Python.GetSysModule(engine) >> hostedSys.modules['foobar'] = sys.modules['foobar'] >> >> Is there something I have overlooked here? >> >> As a minor supplementary question, how do I get a reference to the >> default ScriptScope on an engine? Is there any performance advantage in >> using the default one, can I replace it, and does replacing it remove >> any performance benefits we might have got? (OK, so strictly speaking >> that wasn't just one question...) >> >> All the best, >> >> Michael Foord >> >> -- >> Michael Foord >> Senior Software Engineer, Resolver Systems Ltd. >> [EMAIL PROTECTED] >> +44 (0) 20 7253 6372 >> >> Try out Resolver One! <http://www.resolversystems.com/get-it/> >> >> 17a Clerkenwell Road, London EC1M 5RD, UK >> VAT No.: GB 893 5643 79 Registered in England and Wales as company number >> 5467329. >> Registered address: 843 Finchley Road, London NW11 8NA, UK >> >> _______________________________________________ >> Users mailing list >> [email protected] >> http://lists.ironpython.com/listinfo.cgi/users-ironpython.com >> _______________________________________________ >> Users mailing list >> [email protected] >> http://lists.ironpython.com/listinfo.cgi/users-ironpython.com >> >> > > > -- > http://www.ironpythoninaction.com/ > > _______________________________________________ > Users mailing list > [email protected] > http://lists.ironpython.com/listinfo.cgi/users-ironpython.com > _______________________________________________ > Users mailing list > [email protected] > http://lists.ironpython.com/listinfo.cgi/users-ironpython.com > -- http://www.ironpythoninaction.com/ _______________________________________________ Users mailing list [email protected] http://lists.ironpython.com/listinfo.cgi/users-ironpython.com _______________________________________________ Users mailing list [email protected] http://lists.ironpython.com/listinfo.cgi/users-ironpython.com
