Personally, I would shy away from pmods for a new project, instead preferring the tuple module construct with record definitions if the "pmod style function calls" were necessary, this gives you the option of allowing tuple module style calls, while also allowing the more canonical m:f(a) type calls.
And it also let's you take advantage of dialyzer, which cannot be used to properly analyze tuple module calls. If, however, your new project is using CB or boss_db, then you'll be using pmods anyway. -Jesse -- Jesse Gumm Owner, Sigma Star Systems 414.940.4866 || sigma-star.com || @jessegumm On Jul 10, 2014 2:59 AM, "Nicolas Michel" <[email protected]> wrote: > thank you very much ! > very helpful :) (and fun) > > Speaking about P-mod, and being clearly off-topic, it is a good idea to > continue to use P-mod, or to start a new project with P-mod ? > > Nicolas - > > > > 2014-07-09 21:55 GMT+02:00 Jesse Gumm <[email protected]>: > >> If you're curious about the internals of Pmods and their >> implementation (given that that seems to be where this conversation >> has gone), I did a talk a few months ago on "Erlang Gotchas" that >> featured Tuple modules and the now-deprecated Pmods that covers how >> they work within Erlang: It starts with slide number 7: >> http://slides.sigma-star.com/view/Erlang%20Gotchas#/7 >> >> Maybe you'll find it helpful along your path of understanding some of >> Erlang's deep, dark secrets. >> >> -Jesse >> >> On Sat, Jul 5, 2014 at 2:04 PM, Jason Clark <[email protected]> wrote: >> > thanks that makes it a lot clearer >> > >> > >> > On Wednesday, July 2, 2014 7:53:56 AM UTC-7, Igor Clark wrote: >> >> >> >> Hey Jason, mihawk gave a great example there. Not sure if you're new >> to CB >> >> and/or Erlang, but I also found this really confusing when I started >> looking >> >> at CB. >> >> >> >> If you're at all like me it might help to know that the way the models >> >> work is using "parameterized modules", which (if I understand them >> >> correctly) are a way to pass state into a variable when you create it >> >> through parameters on a special "new" function in the module. >> >> >> >> They're kind of controversial in Erlang world as they bring an >> "OO-like" >> >> flavour that many dislike (and argue strongly against), and in fact >> were >> >> removed from the runtime a couple of versions ago, so there's not even >> much >> >> in the way of documentation that comes up in a search >> >> (http://myotherpants.com/2009/04/parameterized-modules-in-erlang/ >> gives a >> >> brief overview, and there are a few notes about them on Stack >> Overflow). >> >> >> >> "P-mods" are pretty core to CB's models though, as they allow >> >> "construction" of "objects" (really just structured variables with >> tuples in >> >> them under the hood) in a Rails-ish way, and so they're still >> supported in >> >> CB by using a "parse transform", which basically converts code using >> them to >> >> non-parameterized "normal" Erlang code. >> >> >> >> So the "new" "method" you're trying to call there is really a >> >> module:function call which requires the extra "constructor"-like >> arguments >> >> mihawk showed in the example in order to "initialize" the variable as a >> >> parameterized module. Once that's done and you have the p-mod variable >> in >> >> play, you can call the module's functions like "accessors" to get hold >> of >> >> the state variables being looked after by the p-mod. >> >> >> >> Like I said I found this really confusing to start because I was >> trying to >> >> get the whole Erlang stateless module:function thing in my head and >> this >> >> seemed to be contrary to that approach; what helped me was to grasp and >> >> remember that what one's really doing with the models (and also >> Requests and >> >> other CB constructed that have parameters in their module definitions) >> is >> >> using some syntactic sugar to help you deal with some state stuff in a >> more >> >> familiar way, if you're coming from e.g. Rails or Django or some other >> >> environment with an ORM. >> >> >> >> Hope this makes sense, and hope others will put me straight if I have >> >> anything wrong! >> >> >> >> Cheers >> >> Igor >> >> >> >> On Tuesday, July 1, 2014 11:15:03 PM UTC-4, mihawk wrote: >> >>> >> >>> hi, >> >>> >> >>> Attrs = [{username, "MyName"},{email "[email protected]"}], >> >>> M = boss_record:new(member, Attrs). >> >>> >> >>> M:username(). >> >>> M:email(). >> >>> >> >>> M1 = M:set(name, "MyName"). >> >>> M1:name(). >> >>> >> >>> M1:save(). >> >>> >> >>> >> >>> >> >>> >> >>> >> >>> >> >>> 2014-07-02 5:28 GMT+08:00 Jason Clark: >> >>>> >> >>>> how do i or can i access a model from the console >> >>>> say i make >> >>>> src/model/member.erl >> >>>> -module(member, [Id, Username, Email, Name, PasswordHash, Key, >> Status]). >> >>>> -define(SECRET_STRING, "Not telling secrets!"). >> >>>> -compile(export_all). >> >>>> >> >>>> %% @doc Returns the session identifier. >> >>>> session_identifier() -> >> >>>> mochihex:to_hex(erlang:md5(?SECRET_STRING ++ Id)). >> >>>> >> >>>> >> >>>> then in the console run >> >>>> member:new(). >> >>>> ** exception error: undefined function member:new/0 >> >>>> >> >>>> member:session_identifier(). >> >>>> ** exception error: undefined function member:session_identifier/0 >> >>>> any ideas >> >>>> im just following the an evening guide but swtched the ward_boss >> >>>> >> >>>> -- >> >>>> You received this message because you are subscribed to the Google >> >>>> Groups "ChicagoBoss" group. >> >>>> To unsubscribe from this group and stop receiving emails from it, >> send >> >>>> an email to >> >>>> Visit this group at http://groups.google.com/group/chicagoboss. >> >>>> To view this discussion on the web visit >> >>>> >> https://groups.google.com/d/msgid/chicagoboss/9c60f373-bcf1-4308-b7fc-b7e7d1c36e8e%40googlegroups.com >> . >> >>>> For more options, visit https://groups.google.com/d/optout. >> >>> >> >>> >> > -- >> > You received this message because you are subscribed to the Google >> Groups >> > "ChicagoBoss" group. >> > To unsubscribe from this group and stop receiving emails from it, send >> an >> > email to [email protected]. >> > Visit this group at http://groups.google.com/group/chicagoboss. >> > To view this discussion on the web visit >> > >> https://groups.google.com/d/msgid/chicagoboss/ee5f5f5a-9675-47ad-a752-ae828c7c2ea4%40googlegroups.com >> . >> > >> > For more options, visit https://groups.google.com/d/optout. >> >> >> >> -- >> Jesse Gumm >> Owner, Sigma Star Systems >> 414.940.4866 || sigma-star.com || @jessegumm >> >> -- >> You received this message because you are subscribed to the Google Groups >> "ChicagoBoss" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> Visit this group at http://groups.google.com/group/chicagoboss. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/chicagoboss/CAPTXyXe3ybyf3_XciLn0w79z8YZHHowxG4uAKYKn7c3ornMUvQ%40mail.gmail.com >> . >> For more options, visit https://groups.google.com/d/optout. >> > > -- > You received this message because you are subscribed to the Google Groups > "ChicagoBoss" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > Visit this group at http://groups.google.com/group/chicagoboss. > To view this discussion on the web visit > https://groups.google.com/d/msgid/chicagoboss/CAAQ9oZo2b8MaCtx8VbNfO67iE5EvQ3FYS8Seq9hjqs5CY0yJHQ%40mail.gmail.com > <https://groups.google.com/d/msgid/chicagoboss/CAAQ9oZo2b8MaCtx8VbNfO67iE5EvQ3FYS8Seq9hjqs5CY0yJHQ%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "ChicagoBoss" group. 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