Prefer XPlot or F# Charting? - f#

I am struggling to understand the difference between XPlot and F# Charting. Each is developed in the context of FsLab, each provides an easy way to display various sorts of charts. Even the syntax seems to be nearly the same.
Maybe it depends on what I want to chart?
In my case I simply would like to display several lines in one chart. I.e. something like
My application has no GUI per se. I just would like to open windows with the charts every now and then while the main application continues execution - or depending on the application's mode, just dump the charts to files.

F# Charting is implemented as a wrapper over System.Windows.Forms.DataVisualization.Charting allowing to use (almost) all of Windows Forms charting capabilities. A cross-platform variant of F# Charting for Mono/.Net implements the same set of capabilities using Gtk.
XPlot is much more feature-rich chart plotting solution based on Google Charts and Plotly javascript libraries, which is cross-platform.
So, if you need just elementary chart combinations and use F# on Windows your best native platform bet is F# Charting.

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How to "structure a web app" in Dart?

I'm starting to study Dart. It seems a nice language and in some aspects a real improvement over JavaScript. Since it claims to come with "batteries included" and to be meant for "structured web apps", though, I fail to understand how to actually structure a web app with it. Almost all the tutorials concentrate on language features, but Dart is quite simple and with many familiar bits, so that's the easy part.
Recently I fell in love with AngularJs. Now routing, two way binding, nested scope, clean separation of concerns... This actually means "structured" to me. But all the Dart examples I find are about selecting HTML elements and attaching listeners to them. This is old-style jQuery-like web programming and quite frankly the opposite of what I think of when I read "structured".
I don't want to compare a language and a framework and I know that Angular Dart is out, but I fear I'm missing something of vanilla Dart, because if it's all about a shorter syntax for lambdas, class based OOP vs prototypical OOP and the like, I don't see how it's supposed to be a game changer: there are many other languages that provide an alternative JS syntax (à la CoffeeScript) and compile to it, and they don't come at the price of losing a perfect integration with existing JavaScript libraries and tools.
Sure, it has optional static typing, which may be great, but this comes more to a matter of preferences. I'm a full time Python and Ruby developer and I'm perfectly fine with dynamic languages. Is this what they mean by "structured"?
Thanks for any clarification that will eventually come.
I work on AngularDart and have some experience structuring web apps.
When building a web app in Dart you would pick a web app framework, for example AngularDart or polymer.dart. Web app frameworks have a lot of opinion which is something that doesn't fit in the core libraries. In that respect, "vanilla Dart" is fairly vanilla.
Since I'm most familiar with Angular, I'll discuss the Angular + Dart combination. However, the rest of this post is also true for polymer.dart.
Angular provides a lot of structure to your app. We've been able to provide a similar structure for both Dart and Javascript. The concept of directives, data binding and dependency injection exist in both.
Dart provides more structure and we've been able to use that structure while building AngularDart. e.g. the directive API is defined in terms of annotations which means that IDEs understand them and can help you code.
There are a number of "structure" features in Dart. One of my favourites is tooling. With types and annotations comes better tooling support.
Types in Dart are most useful when combined with tools. Auto-complete is great but for large web projects, static analyze is even better. For example, in AngularDart, since directives are annotated classes, we can assert that the annotation is correct. Even more interesting is the potential to build tools. In AngularDart, we have a tool that extracts and analyzes all directives. This type of tooling is possible in Javascript but easy and supported by the language in Dart.
libraries, packages
integrated dependency management with pub package manager
class based instead of prototype based
scopes of variables as one would expect in a modern language
static syntax check
better tooling support like code completion

Flex Mobile Project vs. Action script Mobile Project

I am new to development and would like to develop an android application. I have previously built an application with Adobe Flash Builder 4.6 with Flex Mobile Project. I just recently noticed in 4.7 there is an option for Action Script Mobile Project.
Can someone please explain to me the difference between the two and the pros and cons to utilizing either or?
Pros:
Creating a Flex mobile project is easier (use Flex 4.6 with design mode to rapidly prototype, 4.7 to develop) and visually let's you drag and drop
You can use data binding and other convieniant built in tools
Like anything else, there's good and bad about using the Flex mobile project as oppose to a complete ActionScript based solution. Mainly, it's a lot easier to customize your preloadeder, your splash screen and other features similar to tht like customizing how your application handles screen. Below is a couple pros and cons of using the Flex mobile version instead of ActionScript.
Cons:
Slower performance
Can't use Adobe Scout, it's an awesome tool for real time benchmarking and profiling. Using the built in one is ok but it doesn't give you theamazing information that Scout provides.
My advice: if you're savvy enough to do everything in ActionScript, then definitely create an ActionScript project, your users will love you for it. Plus, it's not that much harder and it lets you have a myriad of additional control over your components. Also, you don't have to deal with the overhead that comes with data binding ( it generates event listeners, get and set methods and you can create much more efficient ones on your own). There are a number of other things that benefit you by creating an ActionScript version like refactoring and better subversion but those are more of incentives than anything else.
If you plan on making use of the declarative mark-up, built in UI components, and data binding which the Flex framework provides then you should probably start with a Flex Mobile Project. The downside to this approach is that the additional scaffolding of the Flex framework will incur a slight performance hit and will increase the over-all file size of your project.
On the other hand, if performance is critical and you don't need the declarative markup, built in UI components, or data binding provided by the Flex framework, then you should start with a pure ActionScript mobile project. Really simple applications, games, or applications with highly customised UIs would be examples of projects for which a pure ActionScript approach might be more suitable.
FYI, you can use Adobe Scout on Flex apps. Apache Flex now supports advanced Telemetry.
You can also add advanced telemetry to any SWF with the SWF Scout Enabler.

What's exactly is the web part of delphi web script?

I'm currently starting to integrate "Delphi Web Script" in my application basically only as a scripting engine (interfacing with functions, classes, etc.); awesome software for the standard delphi open source quality in my opinion, but just for curiosity,
What's exactly the "web part" of the project?
How is intended to be used?
It was used somewhere with some success commercially?
Thanks!
As ain said, the original use was for PHP-like, ASP-like server-side web-page generation, but it was also capable of general purpose use, which is what I used it for. And as I did not use the "web" side of DWScript, most of the "web-oriented" features haven't been ported over (only the HTML Filter was ported actually).
The Web functionality is still available in the SourceForge repository, if someone wants to tackle the port. Though, they may be outdated beyond simple renamed methods and classes, as since DWSII, the script engine has gained various features. For instance, it is now capable of multiple thread-safe executions of a single compiled script, while the old codebase is built around the limitation that a compiled script can be executed by only one thread at a time.
On the other hand, there are some new features that could simplify the porting, the simple WebServer demo recently added uses RTTI to expose TWebResponse & TWebRequest f.i. (was manually exposed in DWSII). On the down side, that's only possible with recent Delphi versions.
AFAIK the main focus of the original author of this scripting engine was to make it possible to embed Pascal scripts into HTML pages, just like ie PHP does it. Hence the name "Delphi Web Script". While the focus of the current maintainer, Eric Grange, is on using it as a general purpose scripting engine, it should still be possible to use it for web purposes as well - for that you use the "filters" feature of the library. Check out the dwsHtmlFilter unit for HTML filter.

SmartClient or SmartGWT?

Besides the obvious differences between JavaScript and Java, what are the relevant differences in using either SmartClient or SmartGWT?
SmartGWT is the GWT wrapper for SmartClient, which, as you say, means that you're able to write your SmartGWT app using java.
From my experience the only difference that matters when you're programming is that the GWT wrapper is a bit more restrictive than using the js components directly. For example, programmatically scrolling a TreeGrid from java is hell, since the body of the underlying table (that you need to get at in order to scroll the blasted thing) is not exposed through SmartGWT, while it of course is easily reachable from js.
Overall I wouldn't base the choice between the js components and the gwt wrapper soley on these differences, but I would look at other factors in your project. Which techniques are you most comfortable with? How much custimization are you planning on doing?
In my case, code maintainability.
We are a Python house. But for client-side code we opt for GWT, initially with GXT, but now with SmartGWT.
We don't like Java, but we don't like JS much more, Order, maintain libraries for several widgets, extends objects to give custom functionality, etc. between doing this in JS or Java, the option was obvious, Java side. We write reusable components here, and now we write very minimal code for client side, only reuse components and use REST to comunicate with ours Python backends.
We know that SmartGWT is more verbose than SmartClient, but, with Netbeans autocompletion (some coleagues here use Eclipse) we have direct access to every method, documented, instead to go to the showcase or google every time that we need to test and try new functionality.
SmartGWT provides you the advantage that you may use powerful editors.
You can debug your own code easily (however it's not very helpful for diving into the smartclient code itself).
You have all the auto completion stuff of eclipse/netbeans at hand. When starting to work with SmartClient/Gwt it helps you find the things you are looking for because the editor can list you classes or the available methods and some basic documentation what the class/method actually does. Saves you a lot of time crawling through the docs
Banang : API's to access ListGrid / TreeGrid body are now exposed in Smart GWT.
We chose to use Javascript (no SmartGWT) ... I prefer it that way, although some of our team members (newer to Javascript) would have preferred the SmartGWT way. Both have their pros and cons :
One of the advantages of using SmartGWT, is that you get to have compile time errors since everything gets compiled first by the Java compiler, before it gets rendered to Javascript.
One of the drawbacks of SmartGWT, is that it doesn't expose the full underlying Javascript Smartclient API. This means, if you want to do more advanced stuff, you might end up needing to do it in Javascript anyways.
Another drawback of SmartGWT, productivity wise, is that every single change you do and want to test, needs to go thru the painful Java EE compile/deploy process, whereas if you do it in Javascript, you can alter client side code faster by changing .js files directly without the need for the whole compile/deploy process.
SmartGWT is based on java code and when compiled it transforms it into java script, is a
heavy since it transforms java code into js
SmartClient is a framework based on js, you can use its components in an xml page and you manipulate them in Js, and it’s light
le showcase de smartclient
I recommend smartClient

Metamodelling tools

What tools are available for metamodelling?
Especially for developing diagram editors, at the moment trying out Eclipse GMF
Wondering what other options are out there?
Any comparison available?
Your question is simply too broad for a single answer - due to many aspects.
First, meta-modelling is not a set term, but rather a very fuzzy thing, including modelling models of models and reaching out to terms like MDA.
Second, there are numerous options to developing diagram editors - going the Eclipse way is surely a nice option.
To get you at least started in the Eclipse department:
have a look at MOF, that is architecture for "meta-modelling" from the OMG (the guys, that maintain UML)
from there approach EMOF, a sub set which is supported by the Eclipse Modelling Framework in the incarnation of Ecore.
building something on top of GMF might be indeed a good idea, because that's the way existing diagram editors for the Eclipse platform take (e.g. Omondo's EclipseUML)
there are a lot of tools existing in the Eclipse environment, that can utilize Ecore - I simply hope, that GMF builts on top of Ecore itself.
Dia has an API for this - I was able to fairly trivially frig their UML editor into a basic ER modelling tool by changing the arrow styles. With a DB reversengineering tool I found in sourceforge (took the schema and spat out dia files) you could use this to document databases. While what I did was fairly trivial, the API was quite straightforward and it didn't take me that long to work out how to make the change.
If you're of a mind to try out Smalltalk There used to be a Smalltalk meta-case framework called DOME which does this sort of thing. If you download VisualWorks, DOME is one of the contributed packages.
GMF is a nice example. At the core of this sits EMF/Ecore, like computerkram sais. Ecore is also used for the base of Eclipse's UML2 . The prestige use case and proof of concept for GMF is certainly UML2 Tools.
Although generally a UML tool, I would look at StarUML. It supports additional modules beyond what are already built in. If it doesn't have what you need built in or as a module, I supposed you could make your own, but I don't know how difficult that is.
Meta-modeling is mostly done in Smalltalk.
You might want to take a look at MOOSE (http://moose.unibe.ch). There are a lot of tools being developed for program understanding. Most are Smalltalk based. There is also some java and c++ work.
Two of the most impressive tools are CodeCity and Mondrian. CodeCity can visualize code development over time, Mondrian provides scriptable visualization technology.
And of course there is the classic HotDraw, which is also available in java.
For web development there is also Magritte, providing meta-descriptions for Seaside.
I would strongly recommend you look into DSM (Domain Specific Modeling) as a general topic, meta-modeling is directly related. There are eclipse based tools like GMF that currently require java coding, but integrate nicely with other eclipse tools and UML. However there are two other classes out there.
MetaCase which I will call a pure DSM tool as it focuses on allowing a developer/modeler with out nearly as much coding create a usable graphical model. Additionally it can be easily deployed for others to use. GMF and Microsoft's Beta software factory/DSM tool fall into this category.
Pure Meta-modeling tools which are not intended for DSM tooling, code generation, and the like. I do not follow these tools as closely as I am interested in applications that generate tooling for SMEs, Domain Experts, and others to use and contribute value to an active project not modeling for models sake, or just documentation and theory.
If you want to learn more about number 1, the tooling applications for DSMs/Meta-modeling, then check out my post "DSMForum.org great resources, worth a look." or just navigate directly to the DSMForum.org
In case you are interested in something that is related to modelling and not generation of code, have a look at adoxx.org. As a metamodelling platform it does provide functionalities and mechanisms to quickly develop your own DSL and allows you to focus on the models needs (business requirements, conceptual level design/specification). There is an active community from academia and practice involved developing prototypical as well as commercial application based on the platform. Could be interesting ...

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