pygccxml-development

[pygccxml-development] mdecl and methods that return values

[Allen B. <al...@vr...>]

I just ran into an interesting limitation on the current API.

Namely, when you call methods on mdecl_wrappers and those methods return 
decls for further processing, the return values are ignored.

I ran into in the following case:

my_class = my_namespace["MyClass"]
my_class["mymethod"].exclude()

It could also come up in something else like this though:

similar_classes = my_namespace.classes(re_matcher(".*Proxies"))
similar_classes.member_functions["bad_function"].exclude()

The point is that that the call_redirector_t for mdecl_wrapper doesn't 
return any values from the methods it calls. 

I propose that we refactor this method to build up a list of decls 
returned from all the calls it makes and return them wrapped as a 
mdecl_wrapper_t if there are values returned and if they make sense to 
combine (ie. if they are all decl wrappers).  This should allow 
functionality like above and would add quite a bit of flexibility to 
finding groups of matches within other groups of matches.  (ex: find 
groups of similar methods inside groups of similar classes)

Any comments?

-Allen

Re: [pygccxml-development] mdecl and methods that return values

[Roman Y. <rom...@gm...>]

On 5/30/06, Allen Bierbaum <al...@vr...> wrote:
> I just ran into an interesting limitation on the current API.
>
> Namely, when you call methods on mdecl_wrappers and those methods return
> decls for further processing, the return values are ignored.
>
> I ran into in the following case:
>
> my_class = my_namespace["MyClass"]
> my_class["mymethod"].exclude()

exclude does not have return value

> It could also come up in something else like this though:
>
> similar_classes = my_namespace.classes(re_matcher(".*Proxies"))
> similar_classes.member_functions["bad_function"].exclude()
>
> The point is that that the call_redirector_t for mdecl_wrapper doesn't
> return any values from the methods it calls.
>
> I propose that we refactor this method to build up a list of decls
> returned from all the calls it makes and return them wrapped as a
> mdecl_wrapper_t if there are values returned and if they make sense to
> combine (ie. if they are all decl wrappers).  This should allow
> functionality like above and would add quite a bit of flexibility to
> finding groups of matches within other groups of matches.  (ex: find
> groups of similar methods inside groups of similar classes)

> Any comments?

Allen, I am sorry but I don't understand you. Do you want to know what
declarations
has been [in|ex]cluded? Or you want something more general: to define
return values
for mdecl_wrapper_t for "get" and "call" functionality, as a list of
returned values?

Also, can you modify mdec_wrapper.py  file and send it?

Thanks


-- 
Roman Yakovenko
C++ Python language binding
http://www.language-binding.net/

Re: [pygccxml-development] mdecl and methods that return values

[Allen B. <al...@vr...>]

Roman Yakovenko wrote:

> On 5/30/06, Allen Bierbaum <al...@vr...> wrote:
>
>> I just ran into an interesting limitation on the current API.
>>
>> Namely, when you call methods on mdecl_wrappers and those methods return
>> decls for further processing, the return values are ignored.
>>
>> I ran into in the following case:
>>
>> my_class = my_namespace["MyClass"]
>> my_class["mymethod"].exclude()
>
>
> exclude does not have return value

The part that causes the problem is the return from ["mymethod"].  It 
doesn't return anything, so the code above ends up calling exclude() on 
NoneType.

>
>> It could also come up in something else like this though:
>>
>> similar_classes = my_namespace.classes(re_matcher(".*Proxies"))
>> similar_classes.member_functions["bad_function"].exclude()
>>
>> The point is that that the call_redirector_t for mdecl_wrapper doesn't
>> return any values from the methods it calls.
>>
>> I propose that we refactor this method to build up a list of decls
>> returned from all the calls it makes and return them wrapped as a
>> mdecl_wrapper_t if there are values returned and if they make sense to
>> combine (ie. if they are all decl wrappers).  This should allow
>> functionality like above and would add quite a bit of flexibility to
>> finding groups of matches within other groups of matches.  (ex: find
>> groups of similar methods inside groups of similar classes)
>
>
>> Any comments?
>
>
> Allen, I am sorry but I don't understand you. Do you want to know what
> declarations
> has been [in|ex]cluded? 

No.  I want to be able to call methods like decls(), member_functions(), 
classes(), etc on an mdecl_wrapper and have it return another 
mdecl_wrapper.  Right now these would be called but the return values 
would be silently ignored.

> Or you want something more general: to define
> return values
> for mdecl_wrapper_t for "get" and "call" functionality, as a list of
> returned values?

I don't know the answer to this one.  I am interested in getting 
feedback on how other people think this code should function.

>
> Also, can you modify mdec_wrapper.py  file and send it?

Maybe.  I am not sure if I understand everything going on in there so I 
didn't want to take a stab at it and implement it incorrectly.

-Allen

>
> Thanks
>
>

Re: [pygccxml-development] mdecl and methods that return values

[Roman Y. <rom...@gm...>]

On 5/30/06, Allen Bierbaum <al...@vr...> wrote:
> Roman Yakovenko wrote:
>
> > On 5/30/06, Allen Bierbaum <al...@vr...> wrote:
> >
> >> I just ran into an interesting limitation on the current API.
> >>
> >> Namely, when you call methods on mdecl_wrappers and those methods return
> >> decls for further processing, the return values are ignored.
> >>
> >> I ran into in the following case:
> >>
> >> my_class = my_namespace["MyClass"]
> >> my_class["mymethod"].exclude()
> >
> >
> > exclude does not have return value
>
> The part that causes the problem is the return from ["mymethod"].  It
> doesn't return anything, so the code above ends up calling exclude() on
> NoneType.

I will check this and will try to fix.

-- 
Roman Yakovenko
C++ Python language binding
http://www.language-binding.net/

Re: [pygccxml-development] mdecl and methods that return values

[Roman Y. <rom...@gm...>]

> On 5/30/06, Allen Bierbaum <al...@vr...> wrote:
> > Roman Yakovenko wrote:
> > >> my_class = my_namespace["MyClass"]
> > >> my_class["mymethod"].exclude()
> > >
> > >
> > > exclude does not have return value
> >
> > The part that causes the problem is the return from ["mymethod"].  It
> > doesn't return anything, so the code above ends up calling exclude() on
> > NoneType.
>
> I will check this and will try to fix.

Allan, I am sure I am doing something wrong.
I created new test case to check the code: http://tinyurl.com/nlama .
( Please take a look on test__getitem__ method. )
I can not reproduce the bug you are talking about :-)

May be you have scopedef_t.ALLOW_EMPTY_MDECL_WRAPPER set to True?
In this case, if query returns empty exception is not raised.

Can you try and reproduce the bug, thanks ?

-- 
Roman Yakovenko
C++ Python language binding
http://www.language-binding.net/

Re: [pygccxml-development] mdecl and methods that return values

[Allen B. <al...@vr...>]

Roman Yakovenko wrote:

>> On 5/30/06, Allen Bierbaum <al...@vr...> wrote:
>> > Roman Yakovenko wrote:
>> > >> my_class = my_namespace["MyClass"]
>> > >> my_class["mymethod"].exclude()
>> > >
>> > >
>> > > exclude does not have return value
>> >
>> > The part that causes the problem is the return from ["mymethod"].  It
>> > doesn't return anything, so the code above ends up calling 
>> exclude() on
>> > NoneType.
>>
>> I will check this and will try to fix.
>
>
> Allan, I am sure I am doing something wrong.
> I created new test case to check the code: http://tinyurl.com/nlama .
> ( Please take a look on test__getitem__ method. )
> I can not reproduce the bug you are talking about :-)
>
> May be you have scopedef_t.ALLOW_EMPTY_MDECL_WRAPPER set to True?
> In this case, if query returns empty exception is not raised.
>
> Can you try and reproduce the bug, thanks ?
>
I think you are talking about this part of the test:

mb.global_ns[ *'public_base_t'* ].exclude()

Change it to something like this:

mb.global_ns[ *'public_base_t'* ]['myFunction'].exclude()

OR

mb.global_ns[ *'public_base_t'* ].member_functions('myFunction').exclude()


There should be a failure when calling exclude on the value returned 
from the member function lookup because there is nothing returned.  When 
a mdecl_wrapper has a method called upon it, it never returns a value.

Your test works because the only place a mdecl_wrapper comes in is the 
value returned from the ['public_base_t'] call.  This will function fine 
with something like exclude that doesn't return values.  But it will not 
work when you need values returned.

-Allen

Re: [pygccxml-development] mdecl and methods that return values

[Roman Y. <rom...@gm...>]

On 5/30/06, Allen Bierbaum <al...@vr...> wrote:
> I think you are talking about this part of the test:
>
> mb.global_ns[ *'public_base_t'* ].exclude()

Right

> Change it to something like this:
>
> mb.global_ns[ *'public_base_t'* ]['myFunction'].exclude()
>
> OR
>
> mb.global_ns[ *'public_base_t'* ].member_functions('myFunction').exclude()

Now, I don't need unit test. I see why this does not work. Thanks.

Now I know that you want redefine call_redirector_t.__call__ method in next way:

#now
def __call__( self, *arguments, **keywords ):
    for d in self.decls:
        callable_ = getattr(d, self.name)
        callable_( *arguments, **keywords )

#you want:
def __call__( self, *arguments, **keywords ):
    results = []
    for d in self.decls:
        callable_ = getattr(d, self.name)
        answer = callable_( *arguments, **keywords )
        results.append( answer )
    #I assume that all functions will return same type:
    if not results:
        return
    if isinstance( results[0], declaration_t ):
        return mdecl_wrapper_t( results )
    elif isinstance( results[0], mdecl_wrapper_t ):
        temp_decls = []
        for mdecl_wrapper in results:
            temp_decls.extend( mdecl_wrapper.decls )
        return mdecl_wrapper_t( temp_decls )
    else:
        return results

Can you test whether this code will work for you or not?

Thanks

-- 
Roman Yakovenko
C++ Python language binding
http://www.language-binding.net/

Re: [pygccxml-development] mdecl and methods that return values

[Allen B. <al...@vr...>]

Roman Yakovenko wrote:

> On 5/30/06, Allen Bierbaum <al...@vr...> wrote:
>
>> I think you are talking about this part of the test:
>>
>> mb.global_ns[ *'public_base_t'* ].exclude()
>
>
> Right
>
>> Change it to something like this:
>>
>> mb.global_ns[ *'public_base_t'* ]['myFunction'].exclude()
>>
>> OR
>>
>> mb.global_ns[ *'public_base_t'* 
>> ].member_functions('myFunction').exclude()
>
>
> Now, I don't need unit test. I see why this does not work. Thanks.
>
> Now I know that you want redefine call_redirector_t.__call__ method in 
> next way:
>
> #now
> def __call__( self, *arguments, **keywords ):
>    for d in self.decls:
>        callable_ = getattr(d, self.name)
>        callable_( *arguments, **keywords )
>
> #you want:
> def __call__( self, *arguments, **keywords ):
>    results = []
>    for d in self.decls:
>        callable_ = getattr(d, self.name)
>        answer = callable_( *arguments, **keywords )
>        results.append( answer )
>    #I assume that all functions will return same type:
>    if not results:
>        return
>    if isinstance( results[0], declaration_t ):
>        return mdecl_wrapper_t( results )
>    elif isinstance( results[0], mdecl_wrapper_t ):
>        temp_decls = []
>        for mdecl_wrapper in results:
>            temp_decls.extend( mdecl_wrapper.decls )
>        return mdecl_wrapper_t( temp_decls )
>    else:
>        return results
>
> Can you test whether this code will work for you or not?

This is close, but not quite all the code is there.  I have attached a 
diff where I fixed up the implementation and added code to the 
mdecl_wrapper.__getitem__ method to allow calls like I wanted to make.

See attached...


-Allen

>

Re: [pygccxml-development] mdecl and methods that return values

[Roman Y. <rom...@gm...>]

On 5/30/06, Allen Bierbaum <al...@vr...> wrote:
> Roman Yakovenko wrote:
>
> > On 5/30/06, Allen Bierbaum <al...@vr...> wrote:
> >
> >> I think you are talking about this part of the test:
> >>
> >> mb.global_ns[ *'public_base_t'* ].exclude()
> >
> >
> > Right
> >
> >> Change it to something like this:
> >>
> >> mb.global_ns[ *'public_base_t'* ]['myFunction'].exclude()
> >>
> >> OR
> >>
> >> mb.global_ns[ *'public_base_t'*
> >> ].member_functions('myFunction').exclude()
> >
> >
> > Now, I don't need unit test. I see why this does not work. Thanks.
> >
> > Now I know that you want redefine call_redirector_t.__call__ method in
> > next way:
> >
> > #now
> > def __call__( self, *arguments, **keywords ):
> >    for d in self.decls:
> >        callable_ = getattr(d, self.name)
> >        callable_( *arguments, **keywords )
> >
> > #you want:
> > def __call__( self, *arguments, **keywords ):
> >    results = []
> >    for d in self.decls:
> >        callable_ = getattr(d, self.name)
> >        answer = callable_( *arguments, **keywords )
> >        results.append( answer )
> >    #I assume that all functions will return same type:
> >    if not results:
> >        return
> >    if isinstance( results[0], declaration_t ):
> >        return mdecl_wrapper_t( results )
> >    elif isinstance( results[0], mdecl_wrapper_t ):
> >        temp_decls = []
> >        for mdecl_wrapper in results:
> >            temp_decls.extend( mdecl_wrapper.decls )
> >        return mdecl_wrapper_t( temp_decls )
> >    else:
> >        return results
> >
> > Can you test whether this code will work for you or not?
>
> This is close, but not quite all the code is there.  I have attached a
> diff where I fixed up the implementation and added code to the
> mdecl_wrapper.__getitem__ method to allow calls like I wanted to make.
>
> See attached...
>
>
> -Allen
>
> >
>
>
>
> Index: pygccxml_dev/pygccxml/declarations/mdecl_wrapper.py
> ===================================================================
> --- pygccxml_dev/pygccxml/declarations/mdecl_wrapper.py (revision 156)
> +++ pygccxml_dev/pygccxml/declarations/mdecl_wrapper.py (working copy)
> @@ -2,6 +2,7 @@
>  # Distributed under the Boost Software License, Version 1.0. (See
>  # accompanying file LICENSE_1_0.txt or copy at
>  # http://www.boost.org/LICENSE_1_0.txt)
> +import declaration
>
>  class call_redirector_t( object ):
>      """Internal class used to call some function of objects"""
> @@ -11,9 +12,23 @@
>          self.decls = decls
>
>      def __call__( self, *arguments, **keywords ):
> -        for d in self.decls:
> -            callable_ = getattr(d, self.name)
> -            callable_( *arguments, **keywords )
> +       results = []
> +       for d in self.decls:
> +           callable_ = getattr(d, self.name)
> +           answer = callable_( *arguments, **keywords )
> +           results.append( answer )
> +       #I assume that all functions will return same type:
> +       if not results:
> +           return
> +       if isinstance( results[0], declaration.declaration_t ):
> +           return mdecl_wrapper_t( results )
> +       elif isinstance( results[0], mdecl_wrapper_t ):
> +           temp_decls = []
> +           for mdecl_wrapper in results:
> +               temp_decls.extend( mdecl_wrapper.decls )
> +           return mdecl_wrapper_t( temp_decls )
> +       else:
> +           return results
>
>  class mdecl_wrapper_t( object ):
>      """Multiple declarations wrapper.
> @@ -44,8 +59,14 @@
>          return len( self.decls )
>
>      def __getitem__( self, index ):
> -        """provides access to declaration"""
> -        return self.decls[index]
> +        """provides access to declaration.
> +           If passed a standard index, then return contained decl.
> +           Else call the getitem method of contained decls.
> +        """
> +        if isinstance(index, int):
> +            return self.decls[index]
> +        else:
> +            return call_redirector_t( '__getitem__', self.decls)(index)
>
>      def __ensure_attribute( self, name ):
>          invalid_decls = filter( lambda d: not hasattr( d, name ), self.decls )
> @@ -64,4 +85,4 @@
>      def __getattr__( self, name ):
>          """@param name: name of method
>          """
> -        return call_redirector_t( name, self.decls )
> \ No newline at end of file
> +        return call_redirector_t( name, self.decls )
>

Allen, can you send me the whole file? Thanks

-- 
Roman Yakovenko
C++ Python language binding
http://www.language-binding.net/

Re: [pygccxml-development] mdecl and methods that return values

[Roman Y. <rom...@gm...>]

Allen, I tried the patch and there are some errors in unit tests.
I will try to fix it tommorrow and commit. I will let you know.

-- 
Roman Yakovenko
C++ Python language binding
http://www.language-binding.net/

Re: [pygccxml-development] mdecl and methods that return values

[Roman Y. <rom...@gm...>]

On 5/30/06, Roman Yakovenko <rom...@gm...> wrote:
> Allen, I tried the patch and there are some errors in unit tests.
> I will try to fix it tommorrow and commit. I will let you know.

1. __getitem__ has been changed a little:

def __getitem__( self, index ):
        """provides access to declaration.
           If passed a standard index, then return contained decl.
           Else call the getitem method of contained decls.
        """
        if isinstance(index, ( int, slice ) ):
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
            return self.decls[index]
        else:
            return call_redirector_t( '__getitem__', self.decls)(index)

slice has been added.

But still patch does not work:

class X{ X(){} };

global_ns['X'].meber_functions()

Will raise an error: AttributeError: 'constructor_t' object has no
attribute '__getitem__'
The query breaks precondition of
call_redirector_t.__call__ : I assume that all functions will return same type
We don't have list of same objects. So mdecl_wrapper_t.__getitem__ can not
return call_redirector_t( '__getitem__', self.decls)(index) :-(.

Without good definition I don't know how to fix this. So, if you don't
mind I will not apply
the patch.

-- 
Roman Yakovenko
C++ Python language binding
http://www.language-binding.net/

Re: [pygccxml-development] mdecl and methods that return values

[Allen B. <al...@vr...>]

Roman Yakovenko wrote:

> On 5/30/06, Roman Yakovenko <rom...@gm...> wrote:
>
>> Allen, I tried the patch and there are some errors in unit tests.
>> I will try to fix it tommorrow and commit. I will let you know.
>
>
> 1. __getitem__ has been changed a little:
>
> def __getitem__( self, index ):
>        """provides access to declaration.
>           If passed a standard index, then return contained decl.
>           Else call the getitem method of contained decls.
>        """
>        if isinstance(index, ( int, slice ) ):
> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>            return self.decls[index]
>        else:
>            return call_redirector_t( '__getitem__', self.decls)(index)
>
> slice has been added.
>
> But still patch does not work:
>
> class X{ X(){} };
>
> global_ns['X'].meber_functions()
>
> Will raise an error: AttributeError: 'constructor_t' object has no
> attribute '__getitem__'

I would have to look into this further, but what is calling __getitem__ 
on a constructor_t object?

It looks like __getitem__ is being called on a namespace, but that 
should be allowed since a namespace is a scopedef_t.

> The query breaks precondition of
> call_redirector_t.__call__ : I assume that all functions will return 
> same type
> We don't have list of same objects. So mdecl_wrapper_t.__getitem__ can 
> not
> return call_redirector_t( '__getitem__', self.decls)(index) :-(.
>
Maybe the precondition should be modified slightly.  Maybe the 
precondition should be that all objects returned can be wrapped with in 
a mdecl.  So the preconditions would be the same as those for creating 
an mdecl.  And unless I am missing something, an mdecl can wrap objects 
of different types. 

For example a call like:

mfs = my_class.member_functions()

Will return an mdecl that wraps constructors, calldefs, and any other 
types of members.

-Allen

> Without good definition I don't know how to fix this. So, if you don't
> mind I will not apply
> the patch.
>

Re: [pygccxml-development] mdecl and methods that return values

[Roman Y. <rom...@gm...>]

On 5/31/06, Allen Bierbaum <al...@vr...> wrote:
> > class X{ X(){} };
> >
> > global_ns['X'].meber_functions()
> >
> > Will raise an error: AttributeError: 'constructor_t' object has no
> > attribute '__getitem__'
>
> I would have to look into this further, but what is calling __getitem__
> on a constructor_t object?

call_redirector_t.__call__, because: global_ns['X'] is equivalent to
get all declarations
that have name 'X' class and its constructors match the query
I suggest you to debug small example and see what happens.

> > The query breaks precondition of
> > call_redirector_t.__call__ : I assume that all functions will return
> > same type
> > We don't have list of same objects. So mdecl_wrapper_t.__getitem__ can
> > not
> > return call_redirector_t( '__getitem__', self.decls)(index) :-(.
> >
> Maybe the precondition should be modified slightly.  Maybe the
> precondition should be that all objects returned can be wrapped with in
> a mdecl.  So the preconditions would be the same as those for creating
> an mdecl.  And unless I am missing something, an mdecl can wrap objects
> of different types.
>
> For example a call like:
>
> mfs = my_class.member_functions()
>
> Will return an mdecl that wraps constructors, calldefs, and any other
> types of members.

This is how it works right now. The main problem is how to define precondition.

-- 
Roman Yakovenko
C++ Python language binding
http://www.language-binding.net/