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Re: [Pharo-users] How do Smalltalk disambiguate messages?

by Tudor Girba

Hi, : is part of the method name. So, the method: Dictionary>>at: key put: anObject has the name #'at:put:' and the object defining this method will understand a message #âat:put:â. To better understand this, you can play with inspecting the method objects, like below: Does this answer the question? Cheers, Doru > On Oct 16, 2016, at 6:44 AM, CodeDmitry <dimamakhnin(a)gmail.com> wrote: > > I understand that it is a single message send, but to know how to handle the > message at runtime, the parser needs to somehow determine where the > implementation of that message is. It must do a lookup based on multiple > keys(at, and put), which is really confusing. "methods" are easy to look up > because they only have one name, but messages have one name which is split > amongst each argument. > > Simple concatenation does not make sense, since {at: x, put: y} and {a: x, > tput: y} are different messages. > > The only way I can think of this being implemented "easily" is by storing a > table of entries {num_args, arg_names, impl_ref}, and then have the function > "send" do a linear search over this table until it finds an entry with > num_args = 2, each arg_name matching the argument name keys in order, and > then calling the impl_ref with the array of values without the names. > > I'm wondering if there is a way to do this without having to loop over every > single message the object has, then every message its' parent object has, > and so on, just to find which function you actually want to call. > > > > > > -- > View this message in context: http://forum.world.st/How-do-Smalltalk-disambiguate-messages-tp4918946p4918… > Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com. > -- www.tudorgirba.com www.feenk.com "We can create beautiful models in a vacuum. But, to get them effective we have to deal with the inconvenience of reality."

Oct. 16, 2016

Re: [Pharo-users] How do Smalltalk disambiguate messages?

by Charlie Robbats

I think the nub of your confusion is twofold. The method #at:put: is a keyword method and it isn't right to think o them as two keys. It is one compound key and unlike most every other system, Smalltalk keyword message sends allow the programmer to name each argument. This is very fine indeed. The other item is in your thinking that these methods are defined in a prototype chain, like JavaScript. Primarily Smalltalk is a class-based inheritance system for method lookup on message send. What I mean by your example is that when the message #at:put: is sent, the system will start with the concrete class in question, Array, and attempts lookup of #at:put:. When this fails, it then traverses the lookup to the superclass (->ArrayedCollection) and so on on lookup failure (->SequenceableCollection ->Collection ->Object) and at the Object class, the lookup into that Class's methodDictionary succeeds. It tuns out that Object>>#at:put: is a primitive in the vm (#61) that is able to store into an Array object, a variable class and indexable, by the way. Consider the method Array>>atWrap:put: also calling primitive 61. This may help with foundations: http://samizdat.cc/shelf/documents/2004/08.02-historyOfSmalltalk/historyOfS… I hope this helps. On 10/16/2016 12:44 AM, CodeDmitry wrote: > I understand that it is a single message send, but to know how to handle the > message at runtime, the parser needs to somehow determine where the > implementation of that message is. It must do a lookup based on multiple > keys(at, and put), which is really confusing. "methods" are easy to look up > because they only have one name, but messages have one name which is split > amongst each argument. > > Simple concatenation does not make sense, since {at: x, put: y} and {a: x, > tput: y} are different messages. > > The only way I can think of this being implemented "easily" is by storing a > table of entries {num_args, arg_names, impl_ref}, and then have the function > "send" do a linear search over this table until it finds an entry with > num_args = 2, each arg_name matching the argument name keys in order, and > then calling the impl_ref with the array of values without the names. > > I'm wondering if there is a way to do this without having to loop over every > single message the object has, then every message its' parent object has, > and so on, just to find which function you actually want to call. > > > > > > -- > View this message in context: http://forum.world.st/How-do-Smalltalk-disambiguate-messages-tp4918946p4918… > Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com. >

Oct. 16, 2016

Re: [Pharo-users] How do Smalltalk disambiguate messages?

by CodeDmitry

I understand that it is a single message send, but to know how to handle the message at runtime, the parser needs to somehow determine where the implementation of that message is. It must do a lookup based on multiple keys(at, and put), which is really confusing. "methods" are easy to look up because they only have one name, but messages have one name which is split amongst each argument. Simple concatenation does not make sense, since {at: x, put: y} and {a: x, tput: y} are different messages. The only way I can think of this being implemented "easily" is by storing a table of entries {num_args, arg_names, impl_ref}, and then have the function "send" do a linear search over this table until it finds an entry with num_args = 2, each arg_name matching the argument name keys in order, and then calling the impl_ref with the array of values without the names. I'm wondering if there is a way to do this without having to loop over every single message the object has, then every message its' parent object has, and so on, just to find which function you actually want to call. -- View this message in context: http://forum.world.st/How-do-Smalltalk-disambiguate-messages-tp4918946p4918… Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

Oct. 16, 2016

Re: [Pharo-users] How do Smalltalk disambiguate messages?

by Gabriel Cotelli

The message is "at:put:". It's a single message send. I encourage you to try the ProfStef tutorial to understand the basis. On Oct 16, 2016 01:17, "CodeDmitry" <dimamakhnin(a)gmail.com> wrote: > I am trying to do a JavaScript experiment to make Objects behave like > Smalltalk objects. > > example: > > "reminder: Smalltalk arrays start at 1." > |arr| > a := Array new: 1. > a at: 1 put: 'Hello, World'. > > Here, the Smalltalk array has a message "at: index put: value" which is > defined many layers of prototype chaining down, at Object in category > accessing. > > However there are many messages on the way traversing the prototype chain > that start with "at:", such as(SequenceableCollection) "at: x ifAbsent: y", > "at: x incrementBy: y". > > How does Smalltalk tell which message is which? Does it merge the messages > into a single message such as "at: x put: y" to "atPut(x, y)" at some > point? > > Without knowing this, I have to traverse the whole call chain and check > whether each argument is called in a specific way, which is incredibly > expensive. If there was a single name such as "atPut" I can easily just do > a > dictionary lookup for this name and get it at O(1). > > Does Smalltalk actually store each message? > > > > -- > View this message in context: http://forum.world.st/How-do- > Smalltalk-disambiguate-messages-tp4918946.html > Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com. > >

Oct. 16, 2016

How do Smalltalk disambiguate messages?

by CodeDmitry

I am trying to do a JavaScript experiment to make Objects behave like Smalltalk objects. example: "reminder: Smalltalk arrays start at 1." |arr| a := Array new: 1. a at: 1 put: 'Hello, World'. Here, the Smalltalk array has a message "at: index put: value" which is defined many layers of prototype chaining down, at Object in category accessing. However there are many messages on the way traversing the prototype chain that start with "at:", such as(SequenceableCollection) "at: x ifAbsent: y", "at: x incrementBy: y". How does Smalltalk tell which message is which? Does it merge the messages into a single message such as "at: x put: y" to "atPut(x, y)" at some point? Without knowing this, I have to traverse the whole call chain and check whether each argument is called in a specific way, which is incredibly expensive. If there was a single name such as "atPut" I can easily just do a dictionary lookup for this name and get it at O(1). Does Smalltalk actually store each message? -- View this message in context: http://forum.world.st/How-do-Smalltalk-disambiguate-messages-tp4918946.html Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

Oct. 16, 2016

Re: [Pharo-users] location of package SkipLists from ConfigurationOfFuzzySearch?

by HernÃ¡n Morales Durand

Hi Paul, May be SkipLists was included in Pharo images at the time I published the package. You can find it here: http://www.squeaksource.com/skiplists Cheers, HernÃ¡n 2016-10-15 15:39 GMT-03:00 Paul DeBruicker <pdebruic(a)gmail.com>: > Hi Esteban, > > The config stops because the SkipLists package isn't in the FuzzySearcher > repo and whatever repo it is in isn't set as the repository to look in. > Do > you know what repo the SkipLists package is in? > > > Thanks > > Paul > > > EstebanLM wrote > > Hi, > > > > you have a configuration thereâ¦ I didnât tried (so Iâm not sure it will > > work), but I guess you need to use it to have all dependencies loaded. > > > > cheers, > > Esteban > > > >> On 15 Oct 2016, at 20:39, PAUL DEBRUICKER < > > > pdebruic@ > > > > wrote: > >> > >> Hi - > >> > >> I'm trying to load this package > >> http://smalltalkhub.com/#!/~hernan/FuzzySearcher and MC cannot locate > the > >> SkipLists package. Is it published anywhere? > >> > >> > >> Thanks > >> > >> Paul > > > > > > -- > View this message in context: http://forum.world.st/ > location-of-package-SkipLists-from-ConfigurationOfFuzzySearch- > tp4918936p4918938.html > Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com. > >

Oct. 15, 2016

Re: [Pharo-users] location of package SkipLists from ConfigurationOfFuzzySearch?

by Esteban Lorenzano

Hi, you have a configuration thereâ¦ I didnât tried (so Iâm not sure it will work), but I guess you need to use it to have all dependencies loaded. cheers, Esteban > On 15 Oct 2016, at 20:39, PAUL DEBRUICKER <pdebruic(a)gmail.com> wrote: > > Hi - > > I'm trying to load this package http://smalltalkhub.com/#!/~hernan/FuzzySearcher and MC cannot locate the SkipLists package. Is it published anywhere? > > > Thanks > > Paul

Oct. 15, 2016

Re: [Pharo-users] location of package SkipLists from ConfigurationOfFuzzySearch?

by Paul DeBruicker

Hi Esteban, The config stops because the SkipLists package isn't in the FuzzySearcher repo and whatever repo it is in isn't set as the repository to look in. Do you know what repo the SkipLists package is in? Thanks Paul EstebanLM wrote > Hi, > > you have a configuration thereâ¦ I didnât tried (so Iâm not sure it will > work), but I guess you need to use it to have all dependencies loaded. > > cheers, > Esteban > >> On 15 Oct 2016, at 20:39, PAUL DEBRUICKER < > pdebruic@ > > wrote: >> >> Hi - >> >> I'm trying to load this package >> http://smalltalkhub.com/#!/~hernan/FuzzySearcher and MC cannot locate the >> SkipLists package. Is it published anywhere? >> >> >> Thanks >> >> Paul -- View this message in context: http://forum.world.st/location-of-package-SkipLists-from-ConfigurationOfFuz… Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

Oct. 15, 2016

location of package SkipLists from ConfigurationOfFuzzySearch?

by PAUL DEBRUICKER

Hi - I'm trying to load this package http://smalltalkhub.com/#!/~hernan/FuzzySearcher and MC cannot locate the SkipLists package. Is it published anywhere? Thanks Paul

Oct. 15, 2016

Re: [Pharo-users] OSProcess lock image

by Paul DeBruicker

I have no idea why it happens but sometimes OSProcess resumes working after doing a OSProcessAccessor initialize. in a workspace..... Hope this helps HilaireFernandes wrote > Hello, > > On Pharo4, when I type the command: > > OSProcess waitForCommand: 'ls' > > it locks the image, I can get back control with [Alt]-. > > With the same image and VM, this command was previously working, even > called from a Seaside component. > > Any idea? > > Thanks > > Hilaire > > -- > Dr. Geo > http://drgeo.eu -- View this message in context: http://forum.world.st/OSProcess-lock-image-tp4918923p4918935.html Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

Oct. 15, 2016