This looks interesting. I'll be following the development of it On Jun 20, 2013, at 2:56 PM, "Alberto G. Corona " <agocor...@gmail.com> wrote:
> Here is the example with better rendering and additional information as well > as some identifies issues to be solved. > > http://haskell-web.blogspot.com.es/2013/06/the-promising-land-of-monadic-formlets.html > > And I made strong statements there. > > What do you think? If you have questions or want to be involved in the > development of this and other related concepts, please send me a message. > > > 2013/6/20 Alberto G. Corona <agocor...@gmail.com> >> I don´t know how, but the google mail has changed the applicative functor >> operator after (,) Left and Rigth by "<-". >> >> >> >> >> 2013/6/19 Alberto G. Corona <agocor...@gmail.com> >> >>> Hi, >>> >>> This is just to let you know the promising results of some experimentation: >>> >>> Formlets are about applicative instances, but what about monadic instances? >>> What a Monad instance of formlets means? I recently experimented with this >>> and the results are very interesting and powerful- It mixes the best of web >>> forms, with the flexibility of console applications. ???!!!!!! >>> >>> >>> Althoug this example is for the formlets of the MFlow framework , it can be >>> ported to other formlet implementations. Although the MFLow formlets >>> include web formatting that is not supported in other formlets >>> implementations. Static HTML templating don´t work well with monadic >>> formlets, so it is important to include the formatting as a part of the >>> computation: >>> >>> import MFlow.Wai.Blaze.Html.All >>> >>> dynamicForm= wform $ do >>> (n,s) <- (,) <- p << "Who are you?" >>> ++> getString Nothing <! hint "name" <++ br >>> <*> getString Nothing <! hint "surname" <++ br >>> <** submitButton "ok" <++ br >>> >>> flag <- b << "do you " ++> getRadio[radiob "work?",radiob "study?"] >>> <++ br >>> >>> r<-case flag of >>> "work" -> pageFlow "l" >>> $ Left <- b << "do you enjoy your work? " >>> ++> getBool True "yes" "no" >>> <** submitButton "ok" <++ br >>> >>> "study"-> pageFlow "r" >>> $ Right <- b << "do you study in " >>> ++> getRadio[radiob "University" >>> ,radiob "High School"] >>> >>> p << ("You are "++n++" "++s) ++> >>> case r of >>> Left fl -> p << ("You work and it is " ++ show fl ++ " that you >>> enjoy your work") >>> ++> noWidget >>> >>> Right stu -> p << ("You study at the " ++ stu) >>> ++> noWidget >>> >>> >>> hint s= [("placeholder",s)] >>> onClickSubmit= [("onclick","this.form.submit()")] >>> radiob s n= text s ++> setRadio s n <! onClickSubmit >>> >>> Here wform, getBool, getString , getRadio etc are formlet elements >>> >>> The first sentence is an applicative composition that generate a 2 tuple, >>> to show that applicative and monadic can be mixed. the operations ++> add >>> html to the formlet. the operatior <! add attributes to the formlet >>> element.. noWidget is a dumb formlet that does not validate. >>> >>> The second monadic statement is an election between two options. The beauty >>> of the monadic instance is that the rest of the form can vary depending on >>> the previous answers. Since the formlets validate the input, unless the >>> election is made, the radio will not validate, so the monadic execution >>> will be aborted beyond any unanswered question, so nothing will appear >>> after the question. The rest of the form will appear when the user choose >>> one of the two options. once one or the other option is chosen, then >>> another binary question is presented. (either he likes his work or where he >>> study). When the questions are finised, the results are presented. >>> I hope that you get the idea. The benefit is not only the familiar coding >>> and presentation of a sequential console application: Since the form >>> encloses all the fields, At any time the user can change previous inputs >>> and the form will reflect these changes. For example if the user change >>> from work to study (second statements) the "where do you study will appear >>> and the work related questions and answers will disappear. That is >>> wonderfully useful for heavily interactive applications. >>> >>> There is a problem however and it is the issue of the formlet identifiers. >>> Unlike in an applicative presentation, now the number and type of the >>> formlets will vary, so the response to a previous form create a new kind of >>> form, and the post response can be misinterpreted. To avoid that , the >>> pageFlow call creates fixed field labels for each branch of execution. >>> >>> I will release a version of MFlow that support this kind of monadic >>> composition of fomlets, but In essence it is nothing but to add Monad >>> instance to formlets. A single server procedure, that executes the formlet >>> code can support all the interaction so any framework can do it. The >>> usability of that is huge:It is possible to interact in a web page in a >>> console style with questions and answers with the versatitly of a dynamic >>> foms: Any modification in the form change the subsequent flow of >>> interaction. Another application of this monadic style is to ease multistep >>> processes such are registration, check-out and payment ad so on. Even a >>> entire interactive dynamic application can be coded in a single page. >>> >>> And no javascript is needed!. >>> >>> >>> To run this formlet in MFlow: >>> >>> main=do >>> addMessageFlows >>> [("" , transient $ runFlow $ ask dynamicForm )] >>> >>> wait $ run port waiMessageFlow >>> >>> >>> This video show how the presentation of this example vary with the user >>> input: >>> >>> http://youtu.be/DryBQc9agFg >>> >>> >>> I hope that you find the idea interesting. If you want to experiment with >>> this in MFlow, I have to say that the implementation of this feature is in >>> an early stage. The code is in the head branch >>> >>> https://github.com/agocorona/MFlow/tree/head >>> >>> >>> >>> Alberto. >> >> >> >> -- >> Alberto. > > > > -- > Alberto. > _______________________________________________ > web-devel mailing list > web-de...@haskell.org > http://www.haskell.org/mailman/listinfo/web-devel
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