Hi. I think your problem related to the old FFI syntax. In Pharo UFFI is the way to do external calls. To enable old FFI syntax try to switch compiler:
Smalltalk compilerClass: Compiler I used this trick to port some small library which was based on old FFI. I made migration manually but maybe there are tools to convert old FFI methods to new one. 2017-08-16 23:31 GMT+02:00 bdurin <bruno.du...@gmail.com>: > 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. > > 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? > > 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? > > 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. > > Thanks, > Bruno > > > > -- > View this message in context: http://forum.world.st/Parser- > failure-on-FFI-pragmas-declaration-in-Pharo-5-tp4961737.html > Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com. > >
