CORE - Object Instantiation and Location

#ruby 1.9 class Person def initialize(name) @name = name @where = "don't know" # end def report print "\n", @name, " instantiated in: ", @where, "\n" end end p = Person.new("Nancy") p.report - What I'm looking for: how can I detect WHERE the object was instantiated? * module * class * file name * line number * something like def initialize(name) @name = name @where = self.execution.called_from # Object @where = self.execution.file_name # String with filename .. -- http://lazaridis.com

2011/5/26 Ilias Lazaridis <ilias@lazaridis.com>: > > What I'm looking for: > > how can I detect WHERE the object was instantiated? This seems to do what you need. http://snippets.dzone.com/posts/show/2787 See also here: http://www.ruby-doc.org/core/classes/Kernel.html#M001397 -- Roger Braun rbraun.net | humoralpathologie.de

I think you can use class variable like this @@name = name @@where = "don't know" if you initialization then you can get like this way => Nancy ................ Don't knonw -- Posted via http://www.ruby-forum.com/.

On 26 =CE=9C=CE=AC=CF=8A=CE=BF=CF=82, 13:31, Roger Braun <ro...@rogerbraun.= net> wrote: > 2011/5/26 Ilias Lazaridis <il...@lazaridis.com>: > > > > > What I'm looking for: > > > how can I detect WHERE the object was instantiated? > > This seems to do what you need. > > http://snippets.dzone.com/posts/show/2787 Yes, this seems to do it for file/line/method > See also here: > > http://www.ruby-doc.org/core/classes/Kernel.html#M001397 That seems to contain the solution for the function name. And this is the right documentation, but I could not find (within Object and Kernel) the construct I'm looking for (accessing calling Module or Object). #ruby 1.9 class Person def initialize(name) @name =3D name @where =3D self.invoked_from # returns Object end def report print "\n", @name, " instantiated in: ", @where, "\n" end end p =3D Person.new("Nancy") p.report #=3D> Nancy instantiated in: main Is there something like "self.invocation_from", or how could this be implemented? Note that this should work on object model, returning a "living" object. .. -- http://lazaridis.com

On May 26, 2011, at 12:55 , Ilias Lazaridis wrote: > Is there something like "self.invocation_from", or how could this be > implemented? > > Note that this should work on object model, returning a "living" > object. BARRIER - Bad Design Smell

[Note: parts of this message were removed to make it a legal post.] On Thu, May 26, 2011 at 3:53 PM, Ryan Davis <ryand-ruby@zenspider.com>wrote: > > On May 26, 2011, at 12:55 , Ilias Lazaridis wrote: > > > Is there something like "self.invocation_from", or how could this be > > implemented? > > > > Note that this should work on object model, returning a "living" > > object. > > BARRIER - Bad Design Smell > I laughed so hard! Just to make it clear for those following along: this feature would violate multiple principals of object oriented programming and just good design, which is probably why there's not a big push for it. James Edward Gray II

On Thu, May 26, 2011 at 2:35 PM, James Gray <james@graysoftinc.com> wrote: > On Thu, May 26, 2011 at 3:53 PM, Ryan Davis <ryand-ruby@zenspider.com>wro= te: > >> >> On May 26, 2011, at 12:55 , Ilias Lazaridis wrote: >> >> > Is there something like "self.invocation_from", or how could this be >> > implemented? >> > >> > Note that this should work on object model, returning a "living" >> > object. >> >> BARRIER - Bad Design Smell >> > > I laughed so hard! > > Just to make it clear for those following along: =C2=A0this feature would= violate > multiple principals of object oriented programming and just good design, > which is probably why there's not a big push for it. While that's true, lots of Ruby has lots of features that, by default, expose functionality whose use would violate principals of object oriented programming and good design. This is generally a good thing, IMO, because such design principals are generalities and, as such, usually have specific instances in practice where excessive devotion to them is counterproductive. The power to ignore them is often a good thing for a language to have. And, really, a frequently requested feature by Ruby users (which I think was implemented in at least one Gem for pre-1.9 ruby, don't know if there is anything that provides it for 1.9) has been something to the effect of Binding.of_caller that would return the binding of the point from which the current method was called; if such a method existed, Ilias request would seem to just be solved by: Binding.of_caller.eval { self }

On Fri, May 27, 2011 at 7:46 AM, Christopher Dicely <cmdicely@gmail.com> wr= ote: > On Thu, May 26, 2011 at 2:35 PM, James Gray <james@graysoftinc.com> wrote= : >> On Thu, May 26, 2011 at 3:53 PM, Ryan Davis <ryand-ruby@zenspider.com>wr= ote: >> >>> >>> On May 26, 2011, at 12:55 , Ilias Lazaridis wrote: >>> >>> > Is there something like "self.invocation_from", or how could this be >>> > implemented? >>> > >>> > Note that this should work on object model, returning a "living" >>> > object. >>> >>> BARRIER - Bad Design Smell >>> >> >> I laughed so hard! >> >> Just to make it clear for those following along: =C2=A0this feature woul= d violate >> multiple principals of object oriented programming and just good design, >> which is probably why there's not a big push for it. > > While that's true, lots of Ruby has lots of features that, by default, > expose functionality whose use would violate principals of object > oriented programming and good design. This is generally a good thing, > IMO, because such design principals are generalities and, as such, > usually have specific instances in practice where excessive devotion > to them is counterproductive. The power to ignore them is often a good > thing for a language to have. > > And, really, a frequently requested feature by Ruby users (which I > think was implemented in at least one Gem for pre-1.9 ruby, don't know > if there is anything that provides it for 1.9) has been something to > the effect of Binding.of_caller that would return the binding of the > point from which the current method was called; if such a method > existed, Ilias request would seem to just be solved by: > > Binding.of_caller.eval { self } Or, more likely: Binding.of_caller.eval "self"

On 27 =CE=9C=CE=AC=CF=8A=CE=BF=CF=82, 17:54, Christopher Dicely <cmdic...@g= mail.com> wrote: > On Fri, May 27, 2011 at 7:46 AM, Christopher Dicely <cmdic...@gmail.com> = [...] > > And, really, a frequently requested feature by Ruby users (which I > > think was implemented in at least one Gem for pre-1.9 ruby, don't know > > if there is anything that provides it for 1.9) has been something to > > the effect of Binding.of_caller that would return the binding of the > > point from which the current method was called; if such a method > > existed, Ilias request would seem to just be solved by: > > > Binding.of_caller.eval { self } > > Or, more likely: > > =C2=A0Binding.of_caller.eval "self" http://extensions.rubyforge.org/rdoc/classes/Binding.html http://extensions.rubyforge.org/rdoc/ Yes, this should work, but it seems to have some problems, too: http://www.ruby-forum.com/topic/175402 - There is another solution, which I like more: https://github.com/Asher-/sender found within the answer to this question: http://stackoverflow.com/questions/2016696/getting-module-of-caller-in-ruby - But I try to achieve it without C-level extensions, only with the build in (1.9) object-model / reflection / *documented* call-stack tracing etc. The question is: How to achieve this in a "clean" way, without going to C-level? .. -- http://lazaridis.com

On 27 =CE=9C=CE=AC=CF=8A=CE=BF=CF=82, 07:51, Ilias Lazaridis <il...@lazarid= is.com> wrote: > On 26 =CE=9C=CE=AC=CF=8A=CE=BF=CF=82, 13:31, Roger Braun <ro...@rogerbrau= n.net> wrote: > > > 2011/5/26 Ilias Lazaridis <il...@lazaridis.com>: > > > > What I'm looking for: > > > > how can I detect WHERE the object was instantiated? > > > This seems to do what you need. > > >http://snippets.dzone.com/posts/show/2787 > > > See also here: > > >http://www.ruby-doc.org/core/classes/Kernel.html#M001397 > > This one could lead to a solution, at least a temporal one. > > I can retrieve from the Kernel.caller the call stack, and from there > the information <main>. > > How can I user the string "<main>" or "<class:MyClass>" to retrieve > the actual object of main or MyClass? for "class:MyClass' obj =3D Kernel.const_get("MyClass") #=3D> returns object which represents MyClass for "main"? How can I retrieve the "main" object? .. -- http://lazaridis.com

On Mon, May 30, 2011 at 9:55 AM, Ilias Lazaridis <ilias@lazaridis.com> wrot= e: > On 27 =CC=DC=FA=EF=F2, 07:51, Ilias Lazaridis <il...@lazaridis.com> wrote= : >> On 26 =CC=DC=FA=EF=F2, 13:31, Roger Braun <ro...@rogerbraun.net> wrote: >> >> > 2011/5/26 Ilias Lazaridis <il...@lazaridis.com>: >> >> > > What I'm looking for: >> >> > > how can I detect WHERE the object was instantiated? >> >> > This seems to do what you need. >> >> >http://snippets.dzone.com/posts/show/2787 >> >> > See also here: >> >> >http://www.ruby-doc.org/core/classes/Kernel.html#M001397 >> >> This one could lead to a solution, at least a temporal one. >> >> I can retrieve from the Kernel.caller the call stack, and from there >> the information <main>. >> >> How can I user the string "<main>" or "<class:MyClass>" to retrieve >> the actual object of main or MyClass? > > for "class:MyClass' > > obj =3D Kernel.const_get("MyClass") #=3D> returns object which represents > MyClass > > for "main"? > > How can I retrieve the "main" object? If you are in the top level, then self is that object: puts self puts self.class If not, here is one way: class Test def give_me_main eval 'self', TOPLEVEL_BINDING end end o =3D Test.new.give_me_main puts o puts o.class Jesus.

On 30 =CE=9C=CE=AC=CF=8A=CE=BF=CF=82, 11:06, Jes=C3=BAs Gabriel y Gal=C3=A1= n <jgabrielyga...@gmail.com> wrote: > On Mon, May 30, 2011 at 9:55 AM, Ilias Lazaridis <il...@lazaridis.com> wr= ote: [...] > > for "class:MyClass' > > > obj =3D Kernel.const_get("MyClass") #=3D> returns object which represen= ts > > MyClass > > > for "main"? > > > How can I retrieve the "main" object? [...] > =C2=A0 =C2=A0 eval 'self', TOPLEVEL_BINDING [...] Very nice, this works fine! .. -- http://lazaridis.com

On Mon, May 30, 2011 at 11:05 AM, Ilias Lazaridis <ilias@lazaridis.com> wro= te: > On 30 =CE=9C=CE=AC=CF=8A=CE=BF=CF=82, 11:06, Jes=C3=BAs Gabriel y Gal=C3= =A1n <jgabrielyga...@gmail.com> > wrote: >> On Mon, May 30, 2011 at 9:55 AM, Ilias Lazaridis <il...@lazaridis.com> w= rote: > [...] > >> > for "class:MyClass' >> >> > obj =3D Kernel.const_get("MyClass") #=3D> returns object which represe= nts >> > MyClass >> >> > for "main"? >> >> > How can I retrieve the "main" object? > [...] >> =C2=A0 =C2=A0 eval 'self', TOPLEVEL_BINDING > [...] > > Very nice, this works fine! The approach is broken because you will never properly track anonymous objects. E.g. class Bar; end class Factory def create Bar.new end end bar =3D Factory.new.create # now our creator is gone If you want to make this traceable you will keep significantly more objects alive than without creation tracking. I suggest you settle with file and line number which should be sufficient in the general case to identify the source location. With a bit of coding you can even make this very memory savvy so the overhead is far less than if you keep hold on the creator instance. Cheers robert --=20 remember.guy do |as, often| as.you_can - without end http://blog.rubybestpractices.com/

On 30 =CE=9C=CE=AC=CF=8A=CE=BF=CF=82, 18:00, Robert Klemme <shortcut...@goo= glemail.com> wrote: [...] - (setting requirement "anonymous objects", suggesting processing) No need to suggest me requirements and processing. My use-case is solved (I have no requirement for "anonymous objects"). Within this thread, there is a link to solution on C-level (sender), but for now I don't need it. If you know other *existent* libraries which address this issue, please mention it. .. -- http://lazaridis.com

On Tue, May 31, 2011 at 3:40 AM, Ilias Lazaridis <ilias@lazaridis.com> wrot= e: > On 30 =CC=DC=FA=EF=F2, 18:00, Robert Klemme <shortcut...@googlemail.com> = wrote: > [...] - (setting requirement "anonymous objects", suggesting > processing) > > No need to suggest me requirements and processing. Since you didn't post a requirement yourself (you asked for a particular solution) I took the liberty to suggest one commonly seen during debugging. > My use-case is solved (I have no requirement for "anonymous objects"). Glad to see your problem has been solved (whatever it is). Cheers robert --=20 remember.guy do |as, often| as.you_can - without end http://blog.rubybestpractices.com/

On 31 =CE=9C=CE=AC=CF=8A=CE=BF=CF=82, 11:28, Robert Klemme <shortcut...@goo= glemail.com> wrote: > On Tue, May 31, 2011 at 3:40 AM, Ilias Lazaridis <il...@lazaridis.com> wr= ote: > > On 30 =C3=8C=C3=9C=C3=BA=C3=AF=C3=B2, 18:00, Robert Klemme <shortcut...= @googlemail.com> wrote: > > [...] - (setting requirement "anonymous objects", suggesting > > processing) > > > No need to suggest me requirements and processing. > > Since you didn't post a requirement yourself (you asked for a > particular solution) I took the liberty to suggest one commonly seen > during debugging. [...] You are right (subjecting the requirement). I apologize! - Note to readers: I've not verified the quality of this solution, but it seems to be the cleanest implementation (for 1.9) https://github.com/Asher-/sender .. -- http://lazaridis.com