Hi Sebastian, yes, I think some of it is interesting, and the way he focuses on a few benchmarks is not a bad way of classifying GUIs (and toolkits). You just have to remember that his focus is a lot more limited than expected at start: " ... In this thesis we want to investigate if the conclusion of the work on Biglook still holds true or if there are yet novel areas where FP can improve upon OOP in terms of GUI programming and what happens if OOP is completely taken out of the picture " Where Biglook is : " Probably the most directly related paper is “Programming Graphical User Interfaces with Scheme” [18] from 2003 that presents the widget library Biglook that combines object-oriented and classical functional styles for GUI programming " Which is later explained as OOP + Continuations (i.e. Smalltalk-80 style MVC GUI toolkit with blocks). What is generally worrying me in papers on GUI coming from the FP community (and this is not the first one I've seen) is that they are still trying onto recreating properly at best, in FP, the GUIs of the 80's (that is, MVC) (and they have to recreate because they don't want to admit that past great GUIs in FP were done in an abomination to them: a non-statically typed language called Lisp)(and they also conveniently forget the FP nature of Smalltalk on the way there... just look at how this paper makes Smalltalk the same variant of OOP as Java) It's so depressing :( They have good stuff (immutable, persistent structures are certainly a huge boost, as well as FRP) but we'll have to reinvent a GUI toolkit in Smalltalk to show the world how good those concepts are... In the meantime, I remember foundly the MMVC framework in VisualWorks as a very effective toolkit for business GUIs: limited, but effective for what it was intended for. Now, Morphic is so much more powerfull... that we mostly underuse it with basic widgets. Thierry Le 16/02/2015 13:45, Sebastian Sastre a écrit :

Well yes, but is even worst that it doesn’t even mention Douglas Engelbart’s work which is the widely know and hugely influential The Mother of All Demos <https://www.youtube.com/watch?v=yJDv-zdhzMY>/./ / / But the part that is important and I think is valid is the one that shows gradually how a GUI framework deals with incremental complexity and learnability.

These examples are a good framework to display a GUI's framework features:

*Counter* Challenges: understanding the basic ideas of a language/toolkit and the essential scaffolding

*Temperature Converter* Challenges: working with bidirectional dataflow, working with user-provided text input

*Flight Booker* Challenges: working with constraints

*Timer* Challenges: working with concurrency, working with competing user/signal interactions, keeping the application responsive

*CRUD* Challenges: separating the domain and presentation logic, managing mutation, building a non-trivial layout

*Circle Drawer* Challenges: implementing undo/redo functionality, custom drawing, implementing dialog control (i.e. keeping the context between successive GUI operations)

*Cells* Challenges: implementing change propagation, customizing a widget, implementing a more authentic/involved GUI application

And these are really good dimensions to benchmark the competitiveness of generic GUI frameworks:

*Dimensions of Evaluation*

The following dimensions of evaluation are a subset of the dimensions from the Cognitive Dimensions of Notations (CDs) <http://www.cl.cam.ac.uk/~afb21/CognitiveDimensions/> framework which is “an approach to analysing the usability of information artefacts”.

*Abstraction Level.* Types and availability of abstraction mechanisms Does the system provide any way of defining new terms within the notation so that it can be extended to describe ideas more clearly? Can details be encapsulated? Does the system insist on defining new terms? What number of new high-level concepts have to be learned to make use of a system? Are they easy to use and easy to learn? Each new idea is a barrier to learning and acceptance but can also make complex code more understandable. For example, Java Swing, the predecessor to JavaFX, employs a variation of the MVC design pattern in its general architecture and in particular for each of its widgets. Such being the case, there is a significant learning requirement to using the widgets reasonably well and often much boilerplate involved (“the system insists on defining new terms”) which does not pay off for simple applications. On the other hand, for very complex applications the MVC-architecture may make the code more understandable and manageable as details can be encapsulated in the new terms “Model, View and Controller”. Another example is a function. A function has a name and, optionally, parameters as well as a body that returns a value following certain computational steps. A client can simply refer to a function by its name without knowing its implementation details. Accordingly, a function abstracts the computational process involved in the computation of a value. The learning barrier to the principle of a function is not great but it can still make a lot of code much more understandable by hiding unimportant details.

*Closeness of Mapping.* Closeness of representations to domain How closely related is the notation to the result it is describing resp. the problem domain? Which parts seem to be a particularly strange way of doing or describing something? An example is the layout definition of a GUI. Languages that do not provide a way to describe the layout in a nested resp. hierarchical manner, and as such force the programmer to “linearize” the code with the introduction of meaningless temporary variables, make it hard to see how the structure of the layout definition relates to the resulting layout of the application. Not for nothing are XML-based view specifications widespread for GUI-toolkits in languages without native support for hierarchical layout expressions.

*Hidden Dependencies.* Important links between entities invisible Are dependencies between entities in the notation visible or hidden? Is every dependency indicated in both directions? Could local changes have confusing global effects? If one entity cites another entity, which in turn cites a third, changing the value of the third entity may have unexpected repercussions. The key aspect is not the fact that A depends on B, but that the dependency is not made visible. A well-known illustration of a bad case of Hidden Dependencies is the fragile base class problem. In (complex) class hierarchies a seemingly safe modification to a base class may cause derived classes to malfunction. The IDE in general cannot help discovering such problems and only certain programming language features can help preventing them. Another example are non-local side-effects in procedures, i.e. the dependencies of a procedure with non-local side-effects are not visible in its signature.

*Error-proneness.* Notation invites mistakes To what extent does the notation influence the likelihood of the user making a mistake? Do some things seem especially complex or difficult (e.g. when combining several things)? In many dynamic languages with implicit definitions of variables a typing error in a variable name can suddenly lead to hard to find errors as the IDE cannot always point out such an error due to the language’s dynamicity. Java’s different calling semantics for primitive and reference types may lead to mistakes if the programmer mixes them up. Implicit null-initialization of variables can lead to null-pointer exceptions if the programmer forgets to correctly initialize a variable before its use.

*Diffuseness.* Verbosity of language How many symbols or how much space does the notation require to produce a certain result or express a meaning? What sorts of things take more space to describe? Some notations can be annoyingly long-winded, or occupy too much valuable “real-estate” within a display area. In Java before version 8 in order to express what are lambdas today anonymous classes were employed. Compared to Java 8’s lambdas these anonymous classes used to be a very verbose way of encoding anonymous functions especially when used in a callback-heavy setting like traditional GUI programming.

*Viscosity.* Resistance to change Are there any inherent barriers to change in the notation? How much effort is required to make a change to a program expressed in the notation? A viscous system needs many user actions to accomplish one goal. Changing the return type of a function might lead to many code breakages in the call sites of said function. In such a case an IDE can be of great help. Creating a conceptual two-way data-binding by means of two callbacks involves more repetition than a more direct way to define such a dependency.

*Commentary* This part is not so much a dimension but a place to mention everything else which is noteworthy and to give a conclusion. For instance, general observations that do not fit into the above dimensions, impressions during the development process, efficiency concerns of the resulting code and potential improvements can be addressed. In addition, the responsibilities of the other dimensions’ results are assigned to the paradigm, language, toolkit and the IDE.

I think Pharo can score high on those, that’s the point of sharing it here

...

On Feb 15, 2015, at 12:08 PM, Thierry Goubier <thierry.goubier@gmail.com <mailto:thierry.goubier@gmail.com>> wrote:

Hi Sebastian,

a guy which starts by saying that no GUI toolkit of significance were written in FP, and forget to link or cite Garnet (by B. Myers) (Common Lisp) is, how to say, intriguing.

Doesn't bode well for the well researched :(

Thierry

Le 15/02/2015 14:08, Sebastian Sastre a écrit :

...

Hi guys,

I saw the interest in GUI lately and today I come across this really well researched master thesis paper that can put some light on how good we can perform in the GUI spectrum in terms of practicality, expressivity and productivity

Introduction

Even though OOP was born with the SIMULA programming language in the 1960s [15], it was Smalltalk that coupled GUI development with the OOP paradigm [25]. Smalltalk’s inventor Alan Kay was inspired by SIMULA, among other influences, to create a new language for graphics-oriented applications leveraging the OOP paradigm – and the rest is history [24]. Ever since Smalltalk successfully showed the promise of OOP for GUI development a great deal of subsequent OOP languages and, particularly, object-oriented GUI toolkits came into existence and eventually into the mainstream. Nearly all mainstream programming languages today directly support the OOP paradigm and there is hardly any widely used GUI toolkit that does not use OOP. Various popular examples of toolkits like Cocoa, WinForms, Qt, wxWidgets, Tk, Swing and GTK+1 all seem to validate the notion of OOP and GUI development being a good fit.

continues: http://www.eugenkiss.com/projects/thesis.pdf

And it seems it triggered this movement of people that are open to receive implementations of the seven dimensions of this benchmark in his repo:

https://github.com/eugenkiss/7guis/wiki

I beleive Pharo can score nicely there and if would be a Pharo implementation there a whole new audience (that we probably aren't reaching now) might take a serious try

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