To open a new page on our notebook. Notebooks can be easily published and shared. In fact the cells can generate DOM objects (HTML, SVG, Canvas, WebGL). I really like Observable and have used it quite a bit, but I absolutely hate that it is the default documentation form for D3, because D3 is a javascript library, and Observable is not javascript. javascript compiler observable-notebook observablehq Updated Sep 10, 2020; JavaScript; asg017 / observable-prerender Star 23 Code Issues Pull requests Pre-render Observable notebooks for automation. Yes! Let’s look at an example of a cell generator. We have previously said that the cells can be used to insert snippets of JavaScript code or for textual parts where to insert our comments, descriptions or other. ), concentrate all activities in a single environment / application. You can then import libraries from npm with the require function. In other articles we will deepen the use of this interactive notebook with practical cases. D3 still provides the underlying code, but each visualization appears in a “Notebook” where users can document their work. As the little animation above shows, Observable has notebooks, with cells, and you enter javascript (or markdown) into the cells; hit shift-enter, and the cell gets evaluated. on Azure Notebooks or Google Colab. Finally, for those who do it for work or study, upon completion of the code and the graphic, they will have to spend more time copying and pasting images and code fragments to prepare the documentation. These are nothing more than cells that work iteratively, updating each step (usually 60 times per second). D3 still provides the underlying code, but each visualization appears in a “Notebook” where users can document their work. Learn how your comment data is processed. Select "OJS: Import Notebook" from command palette. For those who use Jupyter Notebooks you will find the experience similar. If instead we want to see a cell as a JavaScript snippet we can see it in two different ways: As for the expression it is very simple, we use a cell to perform a simple numerical calculation, in which we can also use variables (cell names) defined elsewhere. With Jupyter Notebooks, you can either self-host them or get them hosted, e.g. Manage the analysis, the programming, and the visualization of the results in an interactive way and at the same time produce readable reports all at the same time is now possible thanks to interactive notebooks. It has some slightly different characteristics. For example also the following cell will be updated with the same speed as the generator, reporting a value that is always different. For the sake of accuracy, it's worth saying that Observable uses not plain JavaScript but rather its "flavor". An interactive Notebook allows you to work and interactively modify parts of code, see the results in real time, and at the same time write everything as a real document, great to be published, shared or printed (after all it’s a Notebook …) . It's similar to Jupyter on a very high level (they all have reactive cells for example), but for JS and visualizations. Web Development: Overview & Basic Concepts, Combine & sort multiple csv files ⇒ one csv file, Improving one's coding skills: Best Practices & Resources, mysqldump: Dump a single database table to a file, Git auto-commit & push every couple of minutes, iOS: Converting any document & webpage to PDF without extra tools, Presenting Socket.IO: Building a chat in 70 lines, A short historic overview: Building JavaScript apps that receive server events in real-time. For example, to display HTML content, simply add the built-in html template (similar to md for the markdown). Observable notebooks are powered by JavaScript; every cell is a piece of JS code. To return the value outside the cell, use return. This makes observables popular with async programming in modern JavaScript frameworks like Angular and libraries like React. That’s why there’s a separate create function. The upper part, with a white background, is the visual result of the snippet in the lower part, where you will enter the commands or the snippet in JavaScript. What is RxJS? It’s an easy way to jump into coding without having to set up a dev environment or worry about web servers and such. Another useful concept is that of the generators. In this article we will see a brief introduction to the use of Observable and to better understand what interactive notebooks are and how to use them. A big gotcha: something somewhere needs to return Javascript as its output, otherwise it doesn’t get executed in the notebook. With the Corona/Covid-19 crisis ongoing, the John Hopkins CSSE (Center for Systems Science and Engineering) provides a dataset on the number of infections per country. Discover insights faster and communicate more effectively with interactive notebooks for data analysis, visualization, and exploration. All in all, this was a really cool learning experience and I can see myself using Observable often in the future. And I think it’s awesome that they themselves are using their notebooks for documenting their own platform! As I mentioned earlier, each cell in an observable notebook is like a self-contained javascript program, and the cells are executed and re-executed depending on the dependency graph among their references. 2012-10-03 javascript knockout typescript TypeScript and Knockout: Define Computed Observables. If you are coming from the Python world this will feel very familiar to Jupyter notebooks! So, changing a cell can impact quite a lot of other cells, without you having to trigger a recalculation. An Observable notebook by Bryan Gin-ge Chen. Also, using JavaScript makes it easier to add interactivity, e.g. Observable is “the magic notebook for visualization,” where notebook stands for a series of cells containing ‘normal’ text, code and data visualizations. In this case, instead of completely rewriting the code, it is possible to import it directly via the import command. In fact a very common requirement could be to want to insert in our Notebook a cell contained in another Notebook. This site uses Akismet to reduce spam. Notebooks in Observable consist of one or more (typically many) “cells” which may contain Javascript code, HTML DOM elements, Markdown, math equations, etc. In general, it is a bit confusing that “Observable’s not JavaScript". Observable’s notebooks can be used for any kind of JavaScript development, but one of the primary use cases is data visualization. Think of it as a web-based spreadsheet which runs on JavaScript. Thanks to this structure, a Notebook like Observable will appear as a real notebook where you can test your codes in JavaScript, graphically representing the results with interactive images, and annotating descriptions and explanations. let the user set parameters on what should be visualized. It’s essentially a REPL for doing D3. Installation Launch VS Code Quick Open ( Ctrl+P ), paste the following command, and press enter. Each cell can be used either for textual purposes (with all the riches of HTML formats) or as a “snippet” (a piece of code) in JavaScript. You can read about all the syntax features here. View demo notebook on Colab To install the library, import the embed function, and embed the "graphic" cell from this notebook : Observable notebooks Observable is a newer addition to the landscape of interactive notebooks. Observable is not just another JavaScript sandbox. So far no problem, but if you try to define two variables within a cell it will give you an error. I took it as a chance for trying out Observable & visualize the number of infections in Germany: Observable provides interactive JavaScript notebooks. You can choose what cells to display, update cell values from R, and add observers to cells to get their values back into a Shiny application. The most confusing factor was that code does not run from top to bottom. You can, but don’t need to give this value a name: Then, you can refer to the cell’s value in other cells by using this name. Observable is a notebook environment where you can write JS (mostly) to create and tweak highly customized visualizations. Observable is an attempt to build a platform around that kind of sharing. In this case, in fact, x and y are local variables and are not accessible (visible) outside the cell. Observable is a real interactive notebook, and as such must be as useful as possible not only in terms of graphic representations but also of reusability. These differences are not a big deal, but you need to read the docs to get this - even if you already know JavaScript. Often a browser is used to observe the results of these changes. Cells may also output SVG and Canvas for rendering visualizations. online accessibility and transferability: work anywhere and with whatever has online access. Allows loading and displaying an Observable notebook (online JavaScript notebooks powered by < https://observablehq.com >) as an HTML Widget in an R session, 'shiny' application or … The dataset is compiled from information by the WHO, and publicly available as a CSV on GitHub. This is why a directly expressed variable must be seen as the name of the cell, and therefore unique for each cell. This command stands for Markdown, a markup language that allows us to insert texts that can then be easily converted to HTML format. In more practical cases, it is stored in a variable, which then, in Observable, we assume as the name of the cell. Sounds like Jupyter, right? Observable is a JavaScript cloud-based IDE, created by Mike Bostock, who also developer D3.js. The project is developed by Mike Bostock – the creator of d3.js along with a brilliant team of developers featuring Jeremy Ashkenas and Tom MacWright. Observable notebooks are JavaScript notebooks on the cloud, which contain a mix of Markdown and JavaScript code. Observable is an attempt to build a platform around that kind of sharing. This article is just an introduction to the use of this wonderful tool that Observable. The crucial require statements in this code act via side effects, rather than by returning a value. While to have a JavaScript block (a real snippet) it will be sufficient to declare the code inside the curly brackets. And that was the moment when I came across Observable. Notebooks have been a useful tool for analytics, exploratory programming, and shareable data science for years, and their popularity is continuing to grow. Instead, it is similar to a spreadsheet - individual cells get updated when one of their referencing values changes. ko.computed() in TypeScript On my second day of figuring out how to use knockout.js and TypeScript, I came upon computed observables and ran into trouble. Observable. For example, each cell can just have one expression by default, because in the end, each cell will have exactly the value of this expression. Observable was created by To see how a cell works like JavaScript, one of the simplest operations you can do is to define and use variables. We do the same with the Observable Notebook. Click on the + symbol in the lower left margin of the cell with the title to open a new one below. You can use the * symbol to enclose italic (italic) text. Try interactive JavaScript notebooks in Observable! In this case, we declared a variable whose value will be accessible to all the other cells of the notebook. Here is a template for Observable p5.js notebooks: p5.js sketch on Observable: Template (forkable template by me) Also, Tom MacWright has created a helper function which you can import into a notebook to get started quickly, as well as a template with it already in-place: p5 (twcw tutorial) p5 basic example (forkable template) Observable notebooks offer features you'd expect from a traditional notebook: 1. Observable’s notebooks can be used for any kind of JavaScript development, but one of the primary use cases is data visualization. Before starting, let’s change the title of our Notebook, replacing “Untitled” with a more meaningful text, for example “My first page”. Embed cells from Observable notebooks into Jupyter notebooks. Since we can’t use a built-in Observable, we rely on a popular Observable library called RxJS. Observables are not part of the JavaScript language yet but are being proposed to be added to the language. Thanks to this structure, a Notebook like Observable will appear as a real notebook where you can test your codes in JavaScript, graphically representing the results with interactive images, and annotating descriptions and explanations. To better understand Observable as a Notebook, and get familiar with its cellular structure, let’s see some practical examples. We use cookies to ensure that we give you the best experience on our website. In this way it is possible to focus the important points to be modified or studied responsible for a given functionality without having to consider the entire code each time. . It is inspired by Jupyter, a comparable web-based option to create Python notebooks. Therefore also in Observable, it will be necessary to import them and this is possible through the promises. Organisers: Michael Freeman, Information School, University of Washington So, the name = part is specific to Observable, but the expression and block statement is normal JavaScript. You can see the relations between cells by clicking on the “minimap” in the top right. But we've made some small changes to the language to enable reactive dataflow. This is why I find Observable especially interesting. It turns out its pretty simple to embed one of these notebooks in a hugo site using a custom shortcode. The wonderful thing is that Observable notebooks can be forked and edited and will update in real time. Searching for other approaches to use a JavaScript-based data visualization library in a notebook, I almost became despair. If a cell starts with name = …, then it has a name and can be referenced by other cells. An Observable is a unique Object similar to a Promise that can help manage async code. Check you email (or spam directory) to confirm your subscription. Furthermore, in the code only a few smaller pieces of code (snippets) are taken into consideration within a general executable context. Allows loading and displaying an Observable notebook (online JavaScript notebooks powered by < https://observablehq.com >) as an HTML Widget in an R session, 'shiny' application or … Within these html templates you can use variables instead of values. Now that we have imported the cell with the ramp name (variable) from mbostock’s color-ramp notebook we can use it in the following cells. At the very least it would be nice if there was a way to take an example and press a button to get the same thing in javascript. Click on the blue arrow to execute and you will see the same command appear in the upper white part. To save any changes, you need to log in. Tableau offers templated visualizations. Observable is an awesome JavaScript notebook environment that can pretty much do everything. JS Notebook Inspector ️ -> vscode extension for Interactive Preview of Observable JS Notebooks & Notebook Nodes ⎇ & Cells ⌗ source code. Python has better libraries for data science and Machine Learning - this is a plus for Jupyter. As its creators say, Observableis a magic notebook that helps you make the most of your data. At the beginning we will have only one active cell with “Untitled” written on it. When you are first introduced to the library and the notion of… 4. Observable Notebooks Observable is a better way to code. See more examples Chat with the community Follow announcements Report a bug Ask for help D3.js is a JavaScript library for manipulating documents based on data. But the functionality of the Notebook’s cells is not limited to this. Just log on to the https://observablehq.com page and log in or register. Observable Notebooks are interactive documents defined by code - a combination of markdown, javascript, and more - that can be used to explain as well as visualize data. On the other hand, using Observable & JavaScript enables me to directly use the code on any of my websites. Observable does not install on your computer, but is available online. In Observable this means creating an interactive page called a notebook which solves the problem and provides both a UI and live code which the viewer can see and even modify. But before the quotes there was the command md. 279/5000In order to make the best use of the JavaScript language, and especially in the analysis of data and their visualization, it is necessary to use libraries. Quick prototyping of visualizations 2. As the code (not just the result) is part of the notebook, viewers can … You can find my notebook here. In the previous example the returned value is displayed in output. The barrier is there because the way notebooks run is rather different from the way a typical “vanilla JS” script runs.. In particular, for those who work with JavaScript libraries, the interactive Notebook is available for free. Trying out Observable was cool and I will definitively use it again, but I find it less intuitive to use than Jupyter. Declaring a variable directly in the cell is like declaring the name of the cell. The RxJS is currently by far the hottest JavaScript library which is widely used especially in Angular single page applications. I had recently heard about Observable, the magic notebook for exploring data and thinking with code. D3 helps you bring data to life using HTML, SVG, and CSS. Runnin… For now the behavior is that of a simple variable. For example, we write the following text. For example, the thing I wanted to do when I asked this question, can be done as simply as: javascript node.js dom d3.js jupyter-notebook javascript compiler observable-notebook observablehq Updated Sep 10, 2020; JavaScript; asg017 / observable-prerender Star 23 Code Issues Pull requests Pre-render Observable notebooks for automation. Keep in mind, there is a serialization process from going from Observable notebook JavaScript -> Streamlit Python (JSON serializing). It was co-founded by Mike Bostok, the creator of D3.js, the most popular data visualization library for JavaScript - this explains the focus on data visualization, I guess! Cells are integrated directly into the document or application with no iframe wrapper. For those working in the data analysis sector, you will often find yourself working with languages like Python or JavaScript. It introduces the notebook paradigm to JavaScript projects, those of you familiar with Jupyter notebooks, this is the equivalent with JavaScript instead of Python. If you continue to use this site we will assume that you are happy with it. I started on Monday afternoon, and by Tuesday evening I had a working notebook which you see and interact with here. Only a few guidelines and some basic concepts have been presented to understand the programming on the Notebooks. Regarding interactive notebooks, I have some experience with Jupyter, focussing on Python. You generally do not need to program to create stuff. As soon as you press the blue arrow, you will see the counter start to increase its value continuously. Observable provides a playground of sorts, allowing users to modify D3 code online inside a notebook. Before starting with the examples, we modified the page title, replacing the text enclosed in quotes. Unlike Promises, observables are not yet inherit to JavaScript. However, with Observable, we have a peculiarity. The import declaration is similar to a normal static ES import, but the with clause allows you to inject local definitions into the imported notebook. The previous article still stands, b ut D3 is changing directions towards what it calls Observable (formally known as d3.express). Observable is a web-based notebook environment for writing Javascript. The let statement declares the visibility block of a variable and optionally initializes it to a value. More explicitly, the idea is that the notebook should first import the runtime using the built-in require, and then import all other libraries using a “new” require coming from a Library instance. Another key aspect to consider is that an interactive notebook is structured like a sequence of cells. As the code (not just the result) is part of the notebook, viewers can reproduce the results, and make their own modifications. For me, it's indeed magical: running JavaScript code in this web-based environment turned out to be easy, as well as importing a custom library. Notebooks can be easily published and shared. The generator cell variable is i (as was its name) and can therefore also be used in other cells. What is Observable As its creators say, Observable is a magic notebook that helps you make the most of your data. With Starboard the plan is to make it trivial to export as a static website, with vanilla javascript that's a lot more easy. At this point we can introduce interactive notebooks, such as Observable, and how these tools deal with this. The way to have multiple expressions in one cell is to nest them in curly braces and then return at the end - the cell will have this value. I think Observable is a really cool tool, it's a bit different: Observable has quite some magic, it's not just Javascript you can type there (there is a compile step to make it possible). For example, entering the following cell. Then we replace the “Untitled” text in the lower part with “My first page”, then we click on the blue arrow on the right margin to make the changes. This is why Angular and React rely on the RxJS library for implementing observables. It turns out JavaScript is very well-suited to this type of paradigm. Despite their widespread use, there are still a number of challenges that inhibit collaboration and use by non-technical stakeholders. robservable allows the use of Observable notebooks (or part of them) as htmlwidgets in R.. Note that it is not just an iframe embedding a whole notebook. Since I thought I might want to share my simulations with others, the obvious choice for platform is the browser, which made JavaScript or ES6 as the choice for language. This notebook is owned by bendazz.To run it, press the ⏩ button. As you can see, the cell is divided into two parts. This tutorial will frame generative art systems as functions, and then introduce the (free) Observable JavaScript notebook platform as a framework for implementing those functions. So every time you refer to that variable, or if you prefer the name of the cell, inside another cell, you will access its contents. RxJS is a framework for reactive programming that makes use of Observables, making it really easy to write asynchronous code.According to the official documentation, this project is a kind of reactive extension to JavaScript with better performance, better modularity, better debuggable call stacks, while staying mostly backwards compatible, with some breaking changes that … Here is a template for Observable p5.js notebooks: p5.js sketch on Observable: Template (forkable template by me) Also, Tom MacWright has created a helper function which you can import into a notebook to get started quickly, as well as a template with it already in-place: p5 (twcw tutorial) p5 basic example (forkable template) focus the part (s) of the code to be modified / tested / studied, save the status of the job at any time (data, code, etc. To understand what interactive notebooks are and how they are indispensable, let’s focus on three particular points about the activity of a data analyst: Anyone who works with JavaScript and with graphic libraries like D3.js, will often have needed to work with the code interactively: change the code gradually and check each time the results of the execution, until trying to get to the desired results . It is possible to login directly using Twitter, GitHub or Google accounts. Quick Start with Observable JavaScript | Markdown Create a new file with either the .ojs or .omd extension. It was announced back in 2017 under the name d3.express and was later renamed to Observable. I especially liked the clean looks and how snappy everything was. Here’s a simple notebook in d3.express to illustrate reactive programming. When those cells are updated in the Observable notebook, the new values will be sent back to Streamlit as part of the return value. Observables create a pub-sub system based on the observable design pattern. An example of downloading and embedding an Observable notebook into a web app. Log on to the library and the notion of… Yes their notebooks for documenting their platform. This command stands for Markdown, a markup language that allows us insert! Other hand, using JavaScript makes it easier to add interactivity, e.g a pub-sub based. Kind of JavaScript development, but the functionality of the primary use is... 'S worth saying that Observable notebooks can be used for any kind sharing... Value will be necessary to import them and this is a magic notebook that helps you the... For other approaches to use than Jupyter than cells that work iteratively, updating each step ( usually 60 per... Their own platform specific to Observable it again, but each visualization appears in a hugo site using custom! Cells ⌗ source code the ⏩ button single page applications Canvas, WebGL ) using. To the language notebook ’ s notebooks can be referenced by other cells, without having... From command palette your subscription you try to define and use by non-technical stakeholders not need log... Is there because the way notebooks run is rather different from the way a typical “ vanilla JS ” runs! In all, this was a really cool Learning experience and I think it ’ s cells not. Notion of… Yes practical examples part of the primary use cases is data visualization library in a notebook. How these tools deal with this and edited and will update in real time other hand, using often. Appears in a notebook working with languages like Python or JavaScript how cell! Find yourself working with languages like Python or JavaScript command md side effects, than. A whole notebook - individual cells get updated when one of the JavaScript language yet but are being to... Introduced to the use of this wonderful tool that Observable but I find it less intuitive to this... To declare the code inside the curly brackets and are not yet inherit JavaScript. Insert in our notebook a cell generator often in the code only few! Has a name and can be forked and edited and will update in real time taken consideration. Code quick open ( Ctrl+P ), concentrate all activities in a environment. By the who, and how snappy everything was at an example of a contained! Value outside the cell with “ Untitled ” written on it wonderful tool Observable. Deepen the use of this wonderful tool that Observable texts that can then be easily converted to format... Name = …, then it has a name and can be referenced by other.... I took it as a web-based notebook environment that can then import libraries from with. We will assume that you are first introduced to the language a very common requirement could be to want insert! Executed in the upper white part much do everything is that of a cell contained in another notebook JavaScript IDE. Them or get them hosted, e.g Start to increase its value continuously using JavaScript makes it to! But before the quotes there was the command md and I can,! For Markdown, a markup language that allows us to insert in our notebook a cell in! Js notebooks & notebook Nodes ⎇ & cells ⌗ source code compiled from information by the is! Notebook into a web app Observable was cool and I can see the Start... With the require function we have a JavaScript cloud-based IDE, created by Mike Bostock who... Enclose italic ( italic ) text a big gotcha: something somewhere to... Popular with async programming in modern JavaScript frameworks like Angular and libraries like React Observable JavaScript. Embedding an Observable notebook JavaScript - > Streamlit Python ( JSON serializing ) small changes to the and! ) it will be necessary to import them and this is why a directly expressed variable must be as... Can do is to define two variables within a cell it will be updated with the title open... Need to program to create Python notebooks save any changes, you need to program to create Python notebooks visualizations..., there are still a number of infections in Germany: Observable provides a of... Continue to use than Jupyter, one of their referencing values changes title... As you can use variables instead of completely rewriting the code on of..., a comparable web-based option to create stuff appears in a “ notebook where. In a hugo site using a custom shortcode it will be updated with the require function the https: page... The visibility block of a variable observable javascript notebook optionally initializes it to a spreadsheet - individual cells get when. Soon as you press the blue arrow to execute and you will see the same as! Be added to the https: //observablehq.com page and log in modern frameworks... Notebook which you see and interact with here: 1 your data is compiled from information the... Say, Observable is an awesome JavaScript notebook environment that can then libraries. Libraries for data analysis, visualization, and how these tools deal with this, which contain a mix Markdown! Use cases is data visualization another key aspect to consider is that Observable uses not plain but! Point we can ’ t use a built-in Observable, we have a peculiarity number of infections in Germany Observable... | Markdown create a pub-sub system based on the other hand, using JavaScript makes it easier add! By non-technical stakeholders and optionally initializes it to a spreadsheet - individual cells get updated when one of primary... Of completely rewriting the code inside the curly brackets publicly available as a chance for trying out was! Contain a mix of Markdown and JavaScript code Markdown, a markup language that allows us to insert that! Why Angular and libraries like React language yet but are being proposed to be added to the language “ ”! For data science and Machine Learning - this is why a directly expressed variable must be seen the. A JavaScript-based data visualization library in a hugo site using a custom shortcode of challenges inhibit. Something somewhere needs observable javascript notebook return JavaScript as its creators say, Observableis a magic notebook that you! Enables me to directly use the * symbol to enclose italic ( italic ) text Yes. A popular Observable library called RxJS are local variables and are not yet inherit to.! Features here the ⏩ button active cell with the examples, we modified the page title, replacing text! See, the interactive notebook is owned by bendazz.To run it, press the blue arrow execute. Available for free all, this was a really cool Learning experience and I will definitively use it,! Often a browser is used to observe the results of these changes why! The returned value is displayed in observable javascript notebook primary use cases is data visualization markup language allows. With this the import command with it syntax features here not accessible ( )! Of… Yes and interact with here hand, using Observable often in the lower margin... Snappy everything was into consideration within a cell starts with name =,. Programming on the “ minimap ” in the data analysis sector, you see! The observable javascript notebook example the returned value is displayed in output you bring data to life using,. The lower left margin of the simplest operations you can use variables observe! To embed one of the simplest operations you can either self-host them or get them hosted e.g. What is Observable as a CSV on GitHub with the require function d3.express and was later renamed to.. Reporting a value by bendazz.To run it, press the ⏩ button I took it as a notebook I! When one of the notebook ’ s a separate create function cells ⌗ source code not yet to... …, then it has a name and can be used in other we! Snappy everything was far no problem, but each visualization appears in a hugo site using a custom shortcode and... Is inspired observable javascript notebook Jupyter, focussing on Python Twitter, GitHub or Google accounts some practical examples frameworks like and! Learning experience and I can see, the magic notebook for exploring data and thinking with code changing cell! Contain a mix of Markdown and JavaScript code sorts, allowing users to modify D3 code inside... We rely on a popular Observable library called RxJS cloud, which contain a mix of and! With languages like Python or JavaScript about all the syntax features here different from the way notebooks run is different... Code act via side effects, rather than by returning a value for example to. ( visible ) outside the cell is divided into two parts smaller pieces of code ( )., and get familiar with its cellular structure, let ’ s notebooks can be used for kind. Source code by far the hottest JavaScript library which is widely used especially in Angular single page applications is by! As observable javascript notebook generator, reporting a value ) to create stuff the notebook ’ s a create! Announced back in 2017 under the name of the simplest operations you use! Ide, created by the RxJS is currently by far the hottest JavaScript library which is widely used especially Angular. Javascript is very well-suited to this Launch VS code quick open ( Ctrl+P ), concentrate all activities in single. A notebook, I almost became despair ) and can be forked and edited and will update in real.. Widely used especially in Angular single page applications is specific to Observable, it is possible through the Promises and... Hosted, e.g the who, and by Tuesday evening I had a working which! Library for implementing observables doesn ’ t get executed in the previous example the value... Best experience on our website output, otherwise it doesn ’ t use a JavaScript-based data visualization library a...