[cfe-dev] ASTMatchers: isVirtual and isOverride

Gábor Kozár kozargabor at gmail.com
Thu May 16 03:46:33 PDT 2013 

Hi,

> *1. Imagine that I have two files to process in the same execution and
both include the same header file. Will that header file's code be
processed twice? In this case, how could I avoid this?*
*
*
Sorry, this is sounding like you're expecting us to solve all your issues.
You can answer your own question by doing a very simple test, but otherwise
the answer is yes - which is also a no-brainer if you know how the C++
compilation model works. Anyhow, just to give you a pointer: you can store
the FileIDs or filenames already processed, check against this list when
processing a file, and clear this list when starting a new TU. All the
information you need was already mentioned in the mailing list (in fact,
even in this discussion), and you can always refer to the documentation.
*
*
*> But now, I need to find another way to find these cpp files.
*
*
*
Again: RTFM. The SourceManager class is what you need.*
*

> *Is there a way to stop the traversal of the AST in a certain moment
when, for instance, I find what I was looking for?*
*
*
No, as Manuel already mentioned, it's pointless. You can set a flag and
just return from the callback if the flag is true.*
*

Sorry if I'm sounding harsh - I'm more than happy to help with any
reasonable questions, but we've already taught you everything you need. In
fact, you should have been able to learn all this without us - I myself
have learned this mostly through experimentation, reading the documentation
and the Clang source code. This is the way you can learn effectively.

Good luck!

Gabor


2013/5/16 Pedro Delgado Perez <pedro.delgado at uca.es>

>  Hi,
>
> You'll have one process(Decl*) method that does all the common stuff, and
> overloads for more specific types as needed, e.g. process(FunctionDecl*),
> which then call the Decl* overload by explicit casting. Have overload
> resolution work for you.
>
> Ok, I think the best in my case is to have a process method per matcher,
> so don't take care of this anymore.
>
> Now, I have other two or three questions spinning in my mind.
>
> 1. Imagine that I have two files to process in the same execution and both
> include the same header file. Will that header file's code be processed
> twice? In this case, how could I avoid this?
>
> 2. A matcher finds a CXXConstructorDecl node in a header file (we can call
> it X.h):
> -first: I need to inform the cpp files that include X.h that the header
> has changed. How can I find that files? Up to now, I was only proccesing
> one file and searched for the file through
> Context->getSourceManager().getMainFileID() (That I suppose is the file
> which have the main method implemented, but I'm not absolutely sure). But
> now, I need to find another way to find these cpp files.
>
> 3. Is there a way to stop the traversal of the AST in a certain moment
> when, for instance, I find what I was looking for?
>
> Thanks in advance,
>
> Pedro.
>
> *El dia 14 may 2013 21:13, Gábor Kozár <kozargabor at gmail.com> escribió:*
>
> I don't see the problem.
> You'll have one process(Decl*) method that does all the common stuff, and
> overloads for more specific types as needed, e.g. process(FunctionDecl*),
> which then call the Decl* overload by explicit casting. Have overload
> resolution work for you.
> Gabor
>
>
> 2013/5/14 Pedro Delgado Perez <pedro.delgado at uca.es>
>
>> Ok, what I'm trying to do is not to repeat the same code again and again
>> in different methods (process_matcher1(), process_matcher2()...) For
>> example, matcher1 and matcher2 are treated in the same way except in a
>> little part.  At first, I thought of having a Decl* variable and casting
>> the node result, but I'm not sure if this is a good option. Later, for
>> instance, I need to use the getPreviousDecl() method that you told me and
>> then I'll have to know the class type (or maybe I can cast to Decl* again).
>>
>> Pedro.
>> *El dia 14 may 2013 20:15, Gábor Kozár <kozargabor at gmail.com> escribió:*
>>
>> Hi,
>> > *if (Result.Nodes.getNodeAs<clang::CXXConstructorDecl>("matcher1")) {*
>> *
>> *
>> I usually do this:*
>> *
>> if(const CXXConstructorDecl* ctor =
>> Result.Nodes.getNodeAs<CXXConstructorDecl>("matcher1")) { ... }
>> > *template<typename T>
>> void process(const T* Node) {*
>> *
>> *
>> I would recommend against this. Template metaprogramming gives you no
>> advantages here so far as I can see. Use overloading and polymorphism
>> instead.
>> Gabor
>>
>>
>> 2013/5/14 Pedro Delgado Perez <pedro.delgado at uca.es>
>>
>>> Hi,
>>>
>>> Neither :) Just create an object in main(), and hand a pointer to that
>>> object to your callback - then call stuff on it from the match callback.
>>>
>>> Ok, ok, that was the problem.
>>>
>>> > *1. I create a MatchFinder.
>>> > 2. Then, I add two different matchers to the same callback.
>>> > 3. I call run.
>>> >
>>> > My questions are:
>>> > 1. How many times is called the run method? Every time the MatchFinder
>>> finds a node to match?*
>>> *
>>> *
>>> Yes, each time either matcher accepts a node.*
>>> *
>>> > *2. The object callback I add to MatchFinder is created more than
>>> once? When it is deleted?*
>>> *
>>> *
>>> You (the user) are the one responsible for creating and destroying the
>>> callback object. Usually what we do is allocate it on the stack (and pass
>>> it the appropriate arguments, of course), and then pass its address to
>>> MatchFinder. MatchFinder doesn't create, copy or delete your callback
>>> object, so it is safe to store state in the callback.*
>>> *
>>> > *Could you explain better "if the second matcher has no deps on the
>>> information collected by matcher1"?*
>>> *
>>> *
>>> deps = dependencies*
>>> *
>>> *
>>> *
>>> Gabor
>>>
>>> Thanks for your answers Gabor.
>>>
>>> I have decided to follow up the advice of Manuel and I have created a
>>> MatchFinder object with all the matchers and a single MatchCallback object.
>>> So now, I'm in my run() method and I want to know which matcher was bound.
>>> So I think the only way to know this is to ask:
>>>
>>> if (Result.Nodes.getNodeAs<clang::CXXConstructorDecl>("matcher1")){
>>> ...
>>> }
>>> else if(Result.Nodes.getNodeAs<clang::CXXRecordDecl>("matcher2")){
>>> ...
>>> }
>>>
>>> Notice that I'm retrieving different classes of nodes
>>> (clang::CXXConstructorDecl, clang::CXXRecordDecl...) In spite of this fact,
>>> I want to process all the nodes in the same way except from a subtle
>>> difference and I was asking myself if there is a better way I can do
>>> something like this:
>>>
>>> if (Result.Nodes.getNodeAs<clang::CXXConstructorDecl>("matcher1")){
>>>   ...
>>>  process(Result.Nodes.getNodeAs<clang::CXXConstructorDecl>("matcher1"))
>>>
>>> }
>>> else if(Result.Nodes.getNodeAs<clang::CXXRecordDecl>("matcher2")){
>>>  ...
>>>  process(Result.Nodes.getNodeAs<clang::CXXRecordDecl>("matcher2"))
>>> }
>>> ...
>>>
>>> template<typename T>
>>> void process(const T* Node){
>>> ...
>>> }
>>>
>>> Regards,
>>>
>>> Pedro.
>>>
>>> *El dia 10 may 2013 09:21, Gábor Kozár <kozargabor at gmail.com> escribió:*
>>>
>>> Hi,
>>> > *1. I create a MatchFinder.
>>> > 2. Then, I add two different matchers to the same callback.
>>> > 3. I call run.
>>> >
>>> > My questions are:
>>> > 1. How many times is called the run method? Every time the MatchFinder
>>> finds a node to match?*
>>> *
>>> *
>>> Yes, each time either matcher accepts a node.*
>>> *
>>> > *2. The object callback I add to MatchFinder is created more than
>>> once? When it is deleted?*
>>> *
>>> *
>>> You (the user) are the one responsible for creating and destroying the
>>> callback object. Usually what we do is allocate it on the stack (and pass
>>> it the appropriate arguments, of course), and then pass its address to
>>> MatchFinder. MatchFinder doesn't create, copy or delete your callback
>>> object, so it is safe to store state in the callback.*
>>> *
>>> > *Could you explain better "if the second matcher has no deps on the
>>> information collected by matcher1"?*
>>> *
>>> *
>>> deps = dependencies*
>>> *
>>> *
>>> *
>>> Gabor
>>>
>>>
>>> 2013/5/8 Pedro Delgado Perez <pedro.delgadoperez at mail.uca.es>
>>>
>>>> Hi,
>>>>
>>>> Thanks for all your support. I'm going to respond all your
>>>> contributions little by little:
>>>>
>>>> You can execute Matcher1 first, and when it returns, you start
>>>> executing Matcher2. I'm not sure what your problem is exactly. (Of course,
>>>> this will also mean that you will traverse the whole AST twice, which can
>>>> potentially be very expensive.)
>>>>
>>>> Ok. What I don't understand quite well is the order in the execution.
>>>>
>>>> 1. I create a MatchFinder.
>>>> 2. Then, I add two different matchers to the same callback.
>>>> 3. I call run.
>>>>
>>>> My questions are:
>>>> 1. How many times is called the run method? Every time the MatchFinder
>>>> finds a node to match?
>>>> 2. The object callback I add to MatchFinder is created more than once?
>>>> When it is deleted? The problem is that I create the object callback with
>>>> an argument (a constructor method with an argument, not the default
>>>> constructor) and store it in a variable member. However, when the run
>>>> method executes, the value of the variable member is lost and I can't
>>>> understand the problem.
>>>>
>>>> Sorry, missed the comment in one of your more recent emails. So you
>>>> basically want all matches by matcher1 to be found before all matchers by
>>>> matcher2. I think the easiest way to do this is just have two MatchFinder
>>>> classes. Add matcher1 and its callback to the first MatchFinder and call
>>>> run(). Add matcher2 and its callback to the second MatchFinder and call
>>>> run() after the first run() returns. You won't have to reparse the file but
>>>> you will have to traverse the AST twice. There's not much you can do about
>>>> this given the order you want. However, if the second matcher has no deps
>>>> on the information collected by matcher1 you could just get away with a
>>>> single MatchFinder and two callbacks that just store their finds in two
>>>> vectors which you process after run returns
>>>>
>>>> I'm not sure what order you're interested in but you can create two
>>>> match callbacks one to use for each matcher. The callbacks will be called
>>>> in the order the nodes are found in the tree by doing a depth-first
>>>> pre-order traversal as is usual for RecursiveASTVisitor. If both matchers
>>>> match a given node, the callbacks are called in the order they are
>>>> registered.
>>>>
>>>> What sort of order are you looking for?
>>>>
>>>> I understand what you have explained until you say "two callbacks". Why
>>>> could I want to have two different callbacks? Could you explain better "if
>>>> the second matcher has no deps on the information collected by
>>>> matcher1"?
>>>>
>>>>
>>>> What is often faster is to produce a superset of the information needed
>>>> during the traversal / match phase, and then combine / filter the results
>>>> after everything's done...
>>>>
>>>> That is a good solution, I suppose. I will have to study my case more
>>>> in detail to determine whether this fit my problem or not. But, do you
>>>> store all that information in global variables or in the callback object?
>>>>
>>>>
>>>> .
>>>>
>>>> You can just count how many times your match callback is called and
>>>> then print that number after run() returns.
>>>>
>>>> Again, my problem is that I don't $when the match callback is called.
>>>>
>>>> I hope I can end up getting the usage of all this with your help.
>>>>
>>>> Pedro.
>>>>
>>>> *El dia 08 may 2013 12:10, Gábor Kozár <kozargabor at gmail.com> escribió:
>>>> *
>>>>
>>>> Hi,
>>>> > *Ok, this also helps, but the problem is that I need to print
>>>> something when all the nodes have been matched. So, is there a way I can
>>>> check within onStartOfTranslationUnit() method if we have reached the end?
>>>> I have just found this:*
>>>> *
>>>> *
>>>> onStartOfTranslationUnit() is - obviously - called at the start of each
>>>> TU. I.e. this will be called after the previous TU has been completed, i.e.
>>>> all nodes in it have been matched.*
>>>> *
>>>> > *clang::ast_matchers::MatchFinder::ParsingDoneTestCallback*
>>>> *
>>>> *
>>>> This is for testing purposes only, it's not recommended to use it.*
>>>> *
>>>> > *So, what you are saying is that I can't control the order the nodes
>>>> are matched?*
>>>> *
>>>> *
>>>> No, you can't. You'll have to implement a RecursiveASTVisitor manually
>>>> if you need this fine control.*
>>>> *
>>>> > *What I'm trying to explain is that I need all the nodes bound with
>>>> Matcher1 are treated before the execution of nodes bound with Matcher2
>>>> starts.*
>>>> *
>>>> *
>>>> You can execute Matcher1 first, and when it returns, you start
>>>> executing Matcher2. I'm not sure what your problem is exactly. (Of course,
>>>> this will also mean that you will traverse the whole AST twice, which can
>>>> potentially be very expensive.)
>>>> *
>>>> *
>>>> Gabor*
>>>> *
>>>>
>>>>
>>>> 2013/5/8 Pedro Delgado Perez <pedro.delgadoperez at mail.uca.es>
>>>>
>>>>> Hi,
>>>>>
>>>>> You collect information about the matches into e.g. a vector, and you
>>>>> can use the MatchCallback's onStartOfTranslationUnit to process the
>>>>> previous TU's matches.*
>>>>> *
>>>>>
>>>>> Ok, this also helps, but the problem is that I need to print something
>>>>> when *all the nodes* have been matched. So, is there a way I can
>>>>> check within onStartOfTranslationUnit() method if we have reached the end?
>>>>> I have just found this:
>>>>>
>>>>> clang::ast_matchers::MatchFinder::ParsingDoneTestCallback
>>>>>
>>>>> This is the implementation of the class:
>>>>>
>>>>> class ParsingDoneTestCallback<http://fossies.org/dox/clang-3.2.src/classclang_1_1ast__matchers_1_1MatchFinder_1_1ParsingDoneTestCallback.html>{
>>>>>   public:
>>>>>   virtual ~ParsingDoneTestCallback<http://fossies.org/dox/clang-3.2.src/classclang_1_1ast__matchers_1_1MatchFinder_1_1ParsingDoneTestCallback.html#ab6018406e1835b0dcc7fa982e0836a55>
>>>>> ();
>>>>>   virtual void run<http://fossies.org/dox/clang-3.2.src/classclang_1_1ast__matchers_1_1MatchFinder_1_1ParsingDoneTestCallback.html#a818b643aaad117bb86bcda80bba32ceb>()
>>>>> = 0;
>>>>> };
>>>>>
>>>>> Maybe I could redefine the run method. Do you think this may be my
>>>>> solution?
>>>>>
>>>>> So the matchers run regardless of whether you ever access the bound
>>>>> nodes. What this means is that your run() method will be called for every
>>>>> match, with the appropriate nodes bound to the names you defined. So a
>>>>> MatchResult only contains information about one single match (i.e. a
>>>>> subtree of the AST, if you will). Hope this clears things up.
>>>>>
>>>>> Um... I'm a bit mixed up at this moment. So, what you are saying is
>>>>> that I can't control the order the nodes are matched? For me that would be
>>>>> a problem because I need to keep an order in the execution. What I'm trying
>>>>> to explain is that I need all the nodes bound with Matcher1 are treated
>>>>> before the execution of nodes bound with Matcher2 starts.
>>>>>
>>>>> Thanks,
>>>>>
>>>>> Pedro.
>>>>> *El dia 07 may 2013 22:10, Gábor Kozár <kozargabor at gmail.com>
>>>>> escribió:*
>>>>>
>>>>> Hi,
>>>>> >*1. Imagine that I need to print something after all the nodes have
>>>>> been matched. For example, the number of nodes matched. How can I do that?
>>>>> *
>>>>> *
>>>>> *
>>>>> You collect information about the matches into e.g. a vector, and you
>>>>> can use the MatchCallback's onStartOfTranslationUnit to process the
>>>>> previous TU's matches.*
>>>>> *
>>>>> > *How does the 'run' method behave in this case? I mean that I don't
>>>>> know if it retrieves, one by one, all the nodes in applyMatch1 and ,after
>>>>> that, all the nodes in applyMatch2 or it matches one in applyMatch1 and
>>>>> then other in applyMatch2 in each iteration.*
>>>>> *
>>>>> *
>>>>> So the matchers run regardless of whether you ever access the bound
>>>>> nodes. What this means is that your run() method will be called for every
>>>>> match, with the appropriate nodes bound to the names you defined. So a
>>>>> MatchResult only contains information about one single match (i.e. a
>>>>> subtree of the AST, if you will). Hope this clears things up.
>>>>> Gabor
>>>>>
>>>>>
>>>>> 2013/5/7 Pedro Delgado Perez <pedro.delgadoperez at mail.uca.es>
>>>>>
>>>>>> Hi again,
>>>>>>
>>>>>> Sorry to make so much questions, but I hope a good structure of my
>>>>>> tool will save me a lot of time in future.
>>>>>>
>>>>>> I'm using something like this in
>>>>>> http://clang.llvm.org/docs/LibASTMatchersTutorial.html:
>>>>>>
>>>>>> class LoopPrinter : public MatchFinder::MatchCallback {public :  virtual void run(const MatchFinder::MatchResult &Result) {    if (const ForStmt *FS = Result.Nodes.getNodeAs<clang::ForStmt>("forLoop"))      FS->dump();  }};
>>>>>>
>>>>>>
>>>>>> So, now I have two questions:
>>>>>>
>>>>>> 1. Imagine that I need to print something after *all* the nodes have
>>>>>> been matched. For example, the number of nodes matched. How can I do that?
>>>>>>
>>>>>> 2. Imagine that I have two methods within the run method to separate
>>>>>> two kind of nodes I want to bind. Something like this:
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>  class LoopPrinter : public MatchFinder::MatchCallback {public :  virtual void run(const MatchFinder::MatchResult &Result) {    applyMatch1();
>>>>>>
>>>>>>      applyMatch2();  }
>>>>>>
>>>>>> void applyMatch1(){
>>>>>>  if (const ForStmt *FS = Result.Nodes.getNodeAs<clang::ForStmt>("forLoop__1"))
>>>>>>
>>>>>>  }
>>>>>>
>>>>>> void apply2(){
>>>>>>
>>>>>> if (const ForStmt *FS = Result.Nodes.getNodeAs<clang::ForStmt>("forLoop_2"))
>>>>>>
>>>>>> }
>>>>>> };
>>>>>>
>>>>>>
>>>>>>
>>>>>> How does the 'run' method behave in this case? I mean that I don't
>>>>>> know if it retrieves, one by one, all the nodes in applyMatch1 and ,after
>>>>>> that, all the nodes in applyMatch2 or it matches one in applyMatch1 and
>>>>>> then other in applyMatch2 in each iteration. I hope you can understand me
>>>>>> because this is very important in my case.
>>>>>>
>>>>>> Thanks in advance.
>>>>>>
>>>>>> Pedro
>>>>>>
>>>>>>
>>>>>> *El dia 06 may 2013 22:32, "Vane, Edwin" <edwin.vane at intel.com>
>>>>>> escribió:*
>>>>>>
>>>>>> Given your description, I'm not sure matchers are what you want. If
>>>>>> you just want to print information on certain types of nodes, you could use
>>>>>> a RecursiveASTVisitor for that.
>>>>>>
>>>>>> However, if what you're looking for is a little more complex then
>>>>>> matchers may be what you want after all.
>>>>>>
>>>>>> As for the two classes, you want to use tooling::MatchFinder as shown
>>>>>> in the tutorial. The other is just an implementation detail of the match
>>>>>> finding code.
>>>>>>
>>>>>> newASTConsumer() is a function that's required to be defined for
>>>>>> objects passed to newFrontendActionFactory(). You don't need to implement
>>>>>> it. It's implemented by MatchFinder. Again, it's an implementation detail
>>>>>> you don't need to worry about at this point.
>>>>>>
>>>>>> The use of ASTConsumers is not necessary if you're using MatchFinder
>>>>>> and ClangTool as described in the tutorial. MatchFinder is an abstraction
>>>>>> around RecursiveASTVisitor so all that stuff in RecursiveASTVisitor you'd
>>>>>> normally have to use is actually hidden away.
>>>>>>
>>>>>> I think you should first decide which route you want to go:
>>>>>> MatchFinder or RecursiveASTVisitor. The first question I'd ask is: how hard
>>>>>> is it to find the nodes I want to print info on in the AST. If all I want
>>>>>> is every for loop that's easy. If I want for loops within member functions
>>>>>> of a specific class, that's hard and an excellent use case for ASTMatchers.
>>>>>>
>>>>>> -----Original Message-----
>>>>>> From: cfe-dev-bounces at cs.uiuc.edu [mailto:cfe-dev-bounces at cs.uiuc.edu<cfe-dev-bounces at cs.uiuc.edu>]
>>>>>> On
>>>>>> Behalf Of Pedro Delgado Perez
>>>>>> Sent: Monday, May 06, 2013 12:58 PM
>>>>>> To: klimek at google.com; kozargabor at gmail.com
>>>>>> Cc: cfe-dev at cs.uiuc.edu
>>>>>> Subject: Re: [cfe-dev] ASTMatchers: isVirtual and isOverride
>>>>>>
>>>>>> Hi,
>>>>>>
>>>>>> I need your help again. Look, in my tool I was trying to use the
>>>>>> syntax that's
>>>>>> shown here:
>>>>>>
>>>>>> http://clang.llvm.org/docs/LibASTMatchersTutorial.html
>>>>>>
>>>>>> Namely I'm referring to this part:
>>>>>>
>>>>>> int main(int argc, const char **argv) {
>>>>>> CommonOptionsParser OptionsParser(argc, argv);
>>>>>> ClangTool Tool(OptionsParser.getCompilations(),
>>>>>> OptionsParser.getSourcePathList());
>>>>>>
>>>>>> LoopPrinter Printer;
>>>>>> MatchFinder Finder;
>>>>>> Finder.addMatcher(LoopMatcher, &Printer);
>>>>>>
>>>>>> return Tool.run(newFrontendActionFactory(&Finder));
>>>>>> }
>>>>>>
>>>>>> However, now I want to create a object "Printer" with different
>>>>>> features
>>>>>> depending on the arguments provided in command line. So I was
>>>>>> thinking on
>>>>>> implement a factory method pattern to create a different LoopPrinter
>>>>>> object:
>>>>>> class OptionsFactory {
>>>>>> public:
>>>>>> LoopPrinter getOption() {
>>>>>> if(...)
>>>>>> return LoopPrinter(attribute1, attribute2);
>>>>>> else
>>>>>> return LoopPrinter(attribute1);
>>>>>> }
>>>>>> };
>>>>>>
>>>>>> I was searching for a better solution and there are some things that
>>>>>> I can't
>>>>>> completely understand.
>>>>>>
>>>>>> - Why are there two classes MatchFinder:
>>>>>>
>>>>>> http://clang.llvm.org/doxygen/classclang_1_1tooling_1_1MatchFinder.html
>>>>>>
>>>>>> http://clang.llvm.org/doxygen/classclang_1_1ast__matchers_1_1MatchFinder
>>>>>> .
>>>>>> html
>>>>>>
>>>>>> - What the method in ast_matchers:MatchFinder
>>>>>>
>>>>>> clang::ASTConsumer
>>>>>> <http://clang.llvm.org/doxygen/classclang_1_1ASTConsumer.html> *
>>>>>>
>>>>>> newASTConsumer
>>>>>> <
>>>>>> http://clang.llvm.org/doxygen/classclang_1_1ast__matchers_1_1MatchFinder
>>>>>> .html#a4807049e6e39572d19ff127406df3d81> ()
>>>>>>
>>>>>> is used for? I see we can 'associate' an ASTConsumer to the Frontend
>>>>>> as in:
>>>>>> http://clang.llvm.org/docs/RAVFrontendAction.html
>>>>>>
>>>>>> but, is this possible using Matchers? Would it have any sense to
>>>>>> create an
>>>>>> ASTConsumer in my class OptionsFactory?
>>>>>>
>>>>>> I have improved a lot since you last helped me, but clang is too big!
>>>>>>
>>>>>> By the way, do you know how to use CommandLine? I posted a new thread
>>>>>>
>>>>>> http://lists.cs.uiuc.edu/pipermail/cfe-dev/2013-May/029473.html
>>>>>>
>>>>>> If you know how to solve that problem, please, let me know.
>>>>>>
>>>>>> Thanks in advance,
>>>>>>
>>>>>> Pedro.
>>>>>>
>>>>>> El dia 27 abr 2013 18:39, Manuel Klimek <klimek at google.com> escribió:
>>>>>>
>>>>>> On Sat, Apr 27, 2013 at 6:36 PM, Gábor Kozár
>>>>>> <kozargabor at gmail.com> wrote:
>>>>>>
>>>>>>
>>>>>> 2013/4/27 Manuel Klimek <klimek at google.com>
>>>>>>
>>>>>> Just use the empty string for binding and getNodeAs :)
>>>>>>
>>>>>> That would potentially lead to confusion when there are more
>>>>>> nodes bound, but the programmer forgot to supply the proper name. In
>>>>>> my
>>>>>> suggestion, the parameterless getNodeAs would have an assert to check
>>>>>> there is
>>>>>> exactly one node bound (and whose name is the default name).
>>>>>>
>>>>>> If you put everything behind constants, I think it'll be easy enough
>>>>>> to see
>>>>>> what's happening - and that's a generally good strategy anyway, as
>>>>>> you get a
>>>>>> compile error if you mistype...
>>>>>> Thus, I think it'd not add enough value to special case the interface.
>>>>>>
>>>>>>
>>>>>>
>>>>>> 2013/4/27 Manuel Klimek <klimek at google.com>
>>>>>>
>>>>>> On Sat, Apr 27, 2013 at 6:28 PM, Gábor Kozár
>>>>>> <kozargabor at gmail.com> wrote:
>>>>>>
>>>>>> Hi,
>>>>>> 2013/4/26 Pedro Delgado Perez
>>>>>> <pedro.delgadoperez at mail.uca.es>
>>>>>>
>>>>>> Hehehe... I found the problem with
>>>>>> this. I was binding wrongly the matcher! I used a id in the matcher
>>>>>> thas was
>>>>>> different from the id in the function that retrieves the nodes... I
>>>>>> think this will be
>>>>>> a typical mistake for newbies...
>>>>>>
>>>>>> Ah, yes, that happens a lot to me as well. Now
>>>>>> that I think about it, it might be worthwhile adding a parameterless
>>>>>> .bind() and
>>>>>> .getNodeAs<T>() for situations where only one node is bound. Should
>>>>>> be fairly
>>>>>> trivial, but also not all that useful...
>>>>>>
>>>>>> Just use the empty string for binding and getNodeAs :)
>>>>>>
>>>>>>
>>>>>> 2013/4/26 Pedro Delgado Perez
>>>>>> <pedro.delgadoperez at mail.uca.es>
>>>>>>
>>>>>> Thanks both! Now I can see all this
>>>>>> much clearer and I have the enough knowledge to start out with clang.
>>>>>>
>>>>>> You're welcome. Good luck!
>>>>>>
>>>>>> 2013/4/25 Manuel Klimek <klimek at google.com>
>>>>>>
>>>>>> And btw thanks a lot for all the great user support you're giving
>>>>>> here!
>>>>>>
>>>>>> Thank you, I'm happy to help. Clang is a great project!
>>>>>>
>>>>>> As soon as the university term is over, I'm also planning on trying to
>>>>>> contribute code-wise, mainly to the Static Analyzer but I guess also
>>>>>> on just about
>>>>>> anything that catches my attention. :) I'm quite excited - this is
>>>>>> going to be the
>>>>>> first open source project I contribute to.
>>>>>> Gabor
>>>>>>
>>>>>>
>>>>>
>>>>
>>>
>>
>
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