On Thu, Aug 17, 2017 at 1:09 PM, Denis Kudriashov <dionisi...@gmail.com> wrote:
> > Sorry, but we will not accept old pragma format (as I said, is invalid… >> and ugly ;) ). > > > But we will be able load old compiler (when it will be removed from > standard image) to support such old code > But then you should compile such code with the old compiler, not make opal compatible, no? > > 2017-08-17 11:48 GMT+02:00 Esteban Lorenzano <esteba...@gmail.com>: > >> hi, >> >> Old way to do FFI calls is no longer supported on Pharo, but this >> deprecation is very old (since Pharo 2). Now, in Pharo 4 we replaced the >> compiler (for OpalCompiler) and we no longer supported “pragma-like” calls, >> in part because they are “invalid” pragma calls (they do not agrees with >> pragma syntax) and in part because the way to go in pharo is using UFFI >> (before UFFI it was NB which was largely compatible). >> >> I don’t know why ZeroMQ bindings are made using old format, but the way >> to advance them is to >> >> > On 16 Aug 2017, at 23:31, bdurin <bruno.du...@gmail.com> wrote: >> > >> > Hi, >> > >> > I stumbled upon what seems to me a strange issue in Pharo 5. The >> RBParser >> > fails to correctly parse the legacy FFI pragmas. This completely breaks >> down >> > the browser, the inspector and debugger (because as far as I understand >> all >> > use RBParser to correctly highlight syntax). I had the image crashed and >> > some red boxes at some point while insisting to inspect and debug. >> Overall >> > this is not a big issue but it raises some more general bells to me. >> > >> > In order to reproduce this: >> > - load the official Pharo 5 (curl get.pharo.org/50+vm | bash) >> > - launch the image (./pharo-ui Pharo.image &) >> > - add the following repository >> > MCSmalltalkhubRepository >> > owner: 'panuw' >> > project: 'zeromq' >> > user: '' >> > password: '' >> > - load the last versions of ZeroMQ and ConfigurationOfZeroMQ (not sure >> if >> > the latter is needed) >> > - open a Nautilus Browser and look at the class method apiZmqBind:to: >> of the >> > ZmqApi class in the ZeroMQ package: you get a MessageNotUnderstood error >> > (receiver of keywords is nil). You can get past this by clicking on >> > "Abandon" but the source code is displayed in a corrupted way: >> > apiZmqBind: s >> > ocket to: endpoint <cdecl >> > - repeat a few times by looking at other methods until you get a red >> box: >> > then you cannot look at source code any more with this browser. If you >> are >> > obstinate and "lucky" you will succeed in crashing the image. >> > - you can pin the problem by running in a Playground >> > RBParser parseFaultyMethod: 'apiZmqBind: socket to: endpoint >> > <cdecl: long ''zmq_bind'' (ZmqApiSocket* char*) module:''zmq''> >> > ^self externalCallFailed'. >> > and you'll see that the pragmas is not correctly parsed. (The root >> cause is >> > that the legacy adapter RBFFICallPragma does not follow the API defined >> by >> > its super class RBPragmaNode (selector, arguments, positions) and so is >> not >> > a properly defined node. I corrected the problem by computing and >> setting >> > the corresponding instance variables.) >> > >> > 1) As a beginner at Pharo, I find it difficult to deal with the various >> > versions of Pharo. ZeroMQ is the (only) Smalltalk-Pharo binding for >> zmq. It >> > dates back to Feb 2014 so I expected it to work in Pharo as of 3 years >> and a >> > half later (Pharo 6 dates back to June 2017). >> > I naively tried to load the package in a Pharo 6 image and it failed >> because >> > of a syntax error. As I had read a lot about the various FFI >> mechanisms, I >> > quickly understood that it must be because the FFI declarations in >> pragma >> > are not supported anymore. >> > I then loaded the package in a Pharo 5 image and I got the error that I >> > described. After finding the error and solving it, I guess that the FFI >> > declaration in pragma was barely supported in Pharo 5, which has already >> > switched to UFFI and that it is something dating back to Pharo 4. (I >> did not >> > try with Pharo 4 as I do not want to work with versions before 5). >> > Is there a way to know for a package what the compatible Pharo version >> is? >> > It seems that currently I have to look at dates, look at the features >> used >> > by the package and look for the history of development (fortunately the >> > mailing lists are easy to search) to understand which version is likely >> to >> > work. >> > Are not deprecations a bit too fast if a package written 3 years ago >> cannot >> > work in the latest Pharo version and trigger bugs in Pharo 5, which >> dates >> > back to May 2016 (so only a bit more than 2 years after)? >> > I find it a bit too fast as compared to mainstream languages. To my >> mind, >> > either deprecations should be slower or a version/dependencies system >> should >> > be there to help users. >> >> Most of Pharo is largely compatible. Now, we cannot keep compatibility in >> some areas more than a couple of versions back because the effort of >> advance Pharo *and* keep compatibility is just too much. >> - FFI changed a lot. >> - Morphic changed something. >> - Most of the rest is basically the same (just better). >> >> > 2) Another question about versions: Pharo 6 is out since June, Pharo 7 >> is >> > under development. What is the status of Pharo 5? Already history or >> still >> > relevant? >> > I am asking because I corrected the problem of FFI declaration in >> pragma, >> > but it seems to me that it is not useful to publish this change as >> starting >> > from Pharo 6 this way to do FFI is not supported. So should I >> contribute? If >> > yes, how to "attach" the patch to Pharo 5? >> >> Pharo5 is history. >> We keep one version back (now Pharo6) >> Again, a matter of effort and resources. >> >> > 3) As explained above, in Pharo 5, looking at the source trigger an >> error. >> > Even if this looks like a rare corner case, I think that the developer >> tools >> > should not trigger bugs when looking at source code, even less trigger >> a red >> > box in the source code viewer (in the browser, but the problem also >> occurs >> > --less strongly-- when looking at the object in an inspector: there >> should >> > not be "error printing" when it is only a syntax highlight problem). If >> the >> > code is malformed and the parser used to highlight syntax fails, there >> > should be a fallback such as the source code being displayed without any >> > highlight. It sends a very bad impression to have this kind of bugs >> when one >> > simply wants to look at code, not even running it. >> > I have not dug enough in this area of Pharo, but it seems to me that the >> > parser that is used to build the AST for code execution / method >> compilation >> > should not be the same as the parser used to highligh syntax. (Of >> course I >> > am not saying that there should be 2 distincts code base for the 2 >> parsers, >> > but they should at least run differently.) The first one must be strict >> with >> > errors as a malformed AST cannot be executed. The second one must be >> > lenient, as a malformed AST does not prevent to print the string of the >> > source code. Of course, at the end if the code is malformed there will >> be an >> > error at execution, but if the source code can be displayed even when >> it is >> > malformed, at least I have the opportunity to correct it so that it runs >> > correctly. (In this case, convert the old FFI pragma declaration into a >> > fficall:) >> > I may be missing something here but if this works the same in the most >> > up-to-date version of Pharo, the same kind of error might appear again. >> > What do you think? >> >> Sorry, but we will not accept old pragma format (as I said, is invalid… >> and ugly ;) ). >> What I suggest is to rewrite the bindings of ZeroMQ to UFFI: it should be >> very straight forward and you will be contributing to the community in a >> way that will remain quite some years at least. >> > >> > 4) A final remark: let us classify people as Beginner/Confirmed in >> > programming and B/C in Pharo (A BB is a beginner in programming and in >> > Pharo, a CC confirmed in both, a BC cannot exists and CB are those who >> > discover Pharo while knowing well other languages). Pharo seems to be >> great >> > for BB and CC. I went through the MOOC and the various books which are >> > great. My first steps in Pharo environment were great. >> > As a CC it seems to be great also as in the very small area of the >> system >> > where I took the time to drill into all the details, I could very easily >> > change things (and correct a bug), that would have been very difficult >> to >> > understand and change in a lot of other languages. Even hacking the VM >> seems >> > to be possible for a non-VM expert. >> > But I consider myself rather as a CB. As such I tend to try and do >> complex >> > things that I usually do in other languages and run into tricky >> problems. >> > These problems are rather dealt with and corrected by Pharo developers >> but >> > that as a user I would expect them to remain hidden to me or to be >> clearly >> > advertised in the docs. As compared to a BB, a CB is not going to stay >> in a >> > well delimited area where everything is smooth. >> > True, in a way it is a very strong incentive to become a Pharo expert! >> But I >> > am wondering if this aspect could be improved. >> >> thing is… non OO programmers will have problems to understand a pure OO >> language. >> people working with Java, C#, C++ and others may think they do OO, but >> they don’t most of the time… then, switching paradigms is hard work. >> even worst, smalltalk syntax is considered “alien” to people used to >> algol-based languages. >> >> but we cannot do much more than we are trying to achieve in this area: >> make Pharo more compatible with “the rest of the world” when it make sense, >> but strongly stay in our “alieness” when it has sense (syntax, pureness, >> etc.). >> >> Esteban >> >> > >> > Thanks, >> > Bruno >> > >> > >> > >> > -- >> > View this message in context: http://forum.world.st/Parser-f >> ailure-on-FFI-pragmas-declaration-in-Pharo-5-tp4961737.html >> > Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com. >> > >> >> >> > -- Guille Polito Research Engineer French National Center for Scientific Research - *http://www.cnrs.fr* <http://www.cnrs.fr> *Web:* *http://guillep.github.io* <http://guillep.github.io> *Phone: *+33 06 52 70 66 13