Sync with upstream @ 13da0566

.gitattributes

@@ -1 +1,2 @@
 * text=auto eol=lf
+*.svg       binary

1-js/01-getting-started/1-intro/article.md

@@ -1,21 +1,32 @@
 # En introduksjon til JavaScript
 
-Let's see what's so special about JavaScript, what we can achieve with it, and which other technologies play well with it.
+Let's see what's so special about JavaScript, what we can achieve with it, and what other technologies play well with it.
 
 La oss se litt nærmere på hva som er så spesielt med JavaScript, hva vi kan oppnå ved å bruke det, og hvilke andre teknologier som passer godt sammen med det.
 
+<<<<<<< HEAD
 ## Hva er JavaScript?
 
 *JavaScript* var egentlig ment for å *"gi hjemmesider mer liv"*.
+=======
+*JavaScript* was initially created to "make web pages alive".
+
+The programs in this language are called *scripts*. They can be written right in a web page's HTML and run automatically as the page loads.
+>>>>>>> 13da056653754765b50aa5a9f706f84a4a0d6293
 
 Programmer skrevet i JavaScript kalles for *scripts*. De kan skrives rett inn i en nettsides's HTML og kjører automatisk så fort siden blir lastet.
 
 Scripts er utdelt og kjørt som ren tekst. De trenger altså ingen forberedelser eller å bli kompilert for å kjøre.
 
 Med dette øyemed, er JavaScript veldig annerledes fra et annet språk kalt [Java](https://en.wikipedia.org/wiki/Java_(programming_language)).
 
+<<<<<<< HEAD
 ```smart header="Why <u>Java</u>Script?"
 Når JavaScript ble skapt, hadde det i utgangspunktet navnet: "LiveScript". Men Java var veldig populært på den tiden, så det ble bestemt at å presentere et nytt programmeringsspråk som en "lillebror" til Java ville være en god ide.
+=======
+```smart header="Why is it called <u>Java</u>Script?"
+When JavaScript was created, it initially had another name: "LiveScript". But Java was very popular at that time, so it was decided that positioning a new language as a "younger brother" of Java would help.
+>>>>>>> 13da056653754765b50aa5a9f706f84a4a0d6293
 
 Men etterhvert som det utviklet seg ble JavaScript et helt uavhengig programmeringsspårk med sitt eget sett med spesifikasjoner kalt [ECMAScript](http://en.wikipedia.org/wiki/ECMAScript), og nå har det ingenting med Java å gjøre i det hele tatt.
 ```
@@ -27,9 +38,15 @@ Nettleseren har en innebygget motor som noenganger blir kalt for en "JavaScript
 Different engines have different "codenames". For example:
 Det finnes flere forskjellige motorer som har skilles fra hverandre med forskjellige "kodenavn". For eksempel:
 
+<<<<<<< HEAD
 - [V8](https://en.wikipedia.org/wiki/V8_(JavaScript_engine)) -- i Chrome og Opera.
 - [SpiderMonkey](https://en.wikipedia.org/wiki/SpiderMonkey) -- i Firefox.
 - ...Det er også andre kodenavn som "Trident" og "Chakra" for forskjellige versjoner av IE, "ChakraCore" for Microsoft Edge, "Nitro" og "SquirrelFish" for Safari, osv.
+=======
+- [V8](https://en.wikipedia.org/wiki/V8_(JavaScript_engine)) -- in Chrome and Opera.
+- [SpiderMonkey](https://en.wikipedia.org/wiki/SpiderMonkey) -- in Firefox.
+- ...There are other codenames like "Chakra" for IE, "ChakraCore" for Microsoft Edge, "Nitro" and "SquirrelFish" for Safari, etc.
+>>>>>>> 13da056653754765b50aa5a9f706f84a4a0d6293
 
 Begrepene ovenfor er gode å huske fordi de ofte brukt i artikler skrevet av utviklere på nettet. Vi vil bruke de også. For eksempel, hvis "en funksjon x er støttet av v8", vil den sannsynlig fungere i Chrome og Opera.
 
@@ -41,8 +58,12 @@ Motorer er kompliserte. Men det grunnleggende er ganske lett.
 2. Så konverterer den ("kompilerer") scriptet til maskin språk
 3. Og så kjører maskin koden, veldig raskt.
 
+<<<<<<< HEAD
 Motoren tar ibruk optimaliseringer til hver eneste steg i prosessen. Passer til og med på det kompilerte scriptet imens det kjører, analyserer data som flyter gjennom det, og legger så til optimaliseringer til maskin koden basert på denne kunnskapen. 
 Når dette gjøres, kjører scripts rimelig fort.
+=======
+The engine applies optimizations at each step of the process. It even watches the compiled script as it runs, analyzes the data that flows through it, and further optimizes the machine code based on that knowledge.
+>>>>>>> 13da056653754765b50aa5a9f706f84a4a0d6293
 ```
 
 ## Hva kan JavaScript gjøre i nettleseren?
@@ -69,17 +90,29 @@ Eksempler på slike begrensninger inkluderer:
 
 - JavaScript på en nettside kan ikke lese/skrive vilkårlige filer på en harddisk, kopiere eller kjøre programmer. Det har ingen direkte tilgang til funksjoner som er tilknyttet operativsystemet (OS).
 
+<<<<<<< HEAD
     Moderne nettlesere tillater det til å behandle filer, men denne adgangen er begrenset og kun gitt hvis brukeren gjennomfører utvalgte hendelser, som å "slippe" en fil over et nettleservindu eller velger det via en `<input>` tag.
+=======
+- JavaScript on a webpage may not read/write arbitrary files on the hard disk, copy them or execute programs. It has no direct access to OS functions.
+>>>>>>> 13da056653754765b50aa5a9f706f84a4a0d6293
 
     Det finnes måter å interragere med kamera og mikrofon og andre enheter, men disse krever at brukeren gir eksplisitt tillatelse. Så en JavaScript-akrivert side kan ikke på en lumsk måte aktivere webkameraet, se seg rundt og sende informasjonen om dette til [PST](https://no.wikipedia.org/wiki/Politiets_sikkerhetstjeneste).
 
 - Forskjellige paneler/vinduer i en nettleser vet i utgangspunktet ingenting om hverandre. Noenganger gjør de det, for eksempel når et vindu bruker JavaScript til å åpne et annet vindu. Men selv i dette tilfellet, JavaScript fra en side til en kan ikke aksessere et annet vindu hvis det kommer fra forskjellige sider (fra et annet domene, protokoll eller port).
 
+<<<<<<< HEAD
     Dette er kalt "Same Origin Policy". For å jobbe rundt dette, må *begge sidene* inneholde en spesiell JavaScript kode som behandler denne utvekslingen av data.
+=======
+    This is called the "Same Origin Policy". To work around that, *both pages* must agree for data exchange and contain a special JavaScript code that handles it. We'll cover that in the tutorial.
+>>>>>>> 13da056653754765b50aa5a9f706f84a4a0d6293
 
     Denne begrensningen er, igjen satt på plass med brukerens trygghet i tankene. En side fra `http://hvilkensomhelstside.no` som en bruker har åpnet kan overhodet ikke være i stand til å aksessere et annet panel med URL'en `http://gmail.com` og stjele informasjon derfra.
 
+<<<<<<< HEAD
 - JavaScript kan med letthet kommunisere med en tjener over nettet hvor den nåværende siden kom fra. Men dets egenskap til å motta data fra andre sider/domener er veldig tungvint, men det er mulig, dette krever eksplisitt tillatelse (uttrykt via HTTP headere) fra den eksterne siden. Igjen, dette er sikkerhetsbegrensning.
+=======
+![](limitations.svg)
+>>>>>>> 13da056653754765b50aa5a9f706f84a4a0d6293
 
 ![](limitations.svg)
 
@@ -96,9 +129,13 @@ Dette er de *tre* minst gode ting om JavaScript:
 ```
 JavaScript er den eneste nettleser teknologien som kombinerer disse tre tingene.
 
+<<<<<<< HEAD
 Dette er det som gjør JavaScript unikt. Dette er grunnen til at JavaScript er det mest utstrakte verktøyet for utvikling av grensesnitt i nettleseren.
 
 Imens du har planer om å lære deg en teknologi, er det gunstig å sjekke dens perspektiver. Så la oss fortsette til de moderne trendene som påvirker den, inkluderende nye språk og ny nettleser-funksjonalitet.
+=======
+That said, JavaScript also allows to create servers, mobile applications, etc.
+>>>>>>> 13da056653754765b50aa5a9f706f84a4a0d6293
 
 ## Språk "via" JavaScript
 
@@ -112,15 +149,31 @@ Moderne verktøy gjør transpileringen veldig rask og forutsigbar, faktisk så l
 
 Dette er eksempler på slike språk:
 
+<<<<<<< HEAD
 - [CoffeeScript](http://coffeescript.org/) er en "syntaktisk sukker" for JavaScript. Det introduserer kortere syntax, som lar oss skrive klarer og mer presis kode. Ruby utviklere er vanligvis mer glad i dette.
 - [TypeScript](http://www.typescriptlang.org/) er konsentrert rundt å legge til "streng datatyping" for å gjøre utvikling og drifting av komplekse systemer lettere. TypeScript er utviklet av Microsoft.
 - [Dart](https://www.dartlang.org/) er et selvstendig språk som har sin egen motor som kjører ukjente miljøer for nettleseren (som mobilapplikasjoner). Det var i utgangspunktet lagt frem av Google som en erstatter for JavaScript, men foreløpig krever nettlesere at Dart transpileres til JavaScript akkurat som de andre nevnt ovenfor.
 
 Det finnes flere selvfølgelig. Men selv om vi bruker noen av disse språkene, er det lurt av oss å kjenne JavaScript for å vite hva vi egentlig driver med.
+=======
+- [CoffeeScript](http://coffeescript.org/) is a "syntactic sugar" for JavaScript. It introduces shorter syntax, allowing us to write clearer and more precise code. Usually, Ruby devs like it.
+- [TypeScript](http://www.typescriptlang.org/) is concentrated on adding "strict data typing" to simplify the development and support of complex systems. It is developed by Microsoft.
+- [Flow](http://flow.org/) also adds data typing, but in a different way. Developed by Facebook.
+- [Dart](https://www.dartlang.org/) is a standalone language that has its own engine that runs in non-browser environments (like mobile apps), but also can be transpiled to JavaScript. Developed by Google.
+- [Brython](https://brython.info/) is a Python transpiler to JavaScript that enables the writing of applications in pure Python without JavaScript.
+
+There are more. Of course, even if we use one of transpiled languages, we should also know JavaScript to really understand what we're doing.
+>>>>>>> 13da056653754765b50aa5a9f706f84a4a0d6293
 
 ## Summary
 ## Oppsummering
 
+<<<<<<< HEAD
 - JavaScript var i utgangspunktet skapt som et kun-nettleser språk, men finnes også i mange andre miljøer i tillegg.
 - Idag, har JavaScript en unik position som det mest brukt nettleser språket med full integrasjon mot HTML/CSS.
 - Det finnes mange språk som blir "transpilert" til JavaScript og som gir utvalgte funksjoner. Det er anbefalt å ta en kikk på de, ihvertfall ganske kort, etter at du mestrer JavaScript.
+=======
+- JavaScript was initially created as a browser-only language, but it is now used in many other environments as well.
+- Today, JavaScript has a unique position as the most widely-adopted browser language with full integration in HTML/CSS.
+- There are many languages that get "transpiled" to JavaScript and provide certain features. It is recommended to take a look at them, at least briefly, after mastering JavaScript.
+>>>>>>> 13da056653754765b50aa5a9f706f84a4a0d6293

1-js/01-getting-started/2-manuals-specifications/article.md

@@ -0,0 +1,42 @@
+
+# Manuals and specifications
+
+This book is a *tutorial*. It aims to help you gradually learn the language. But once you're familiar with the basics, you'll need other sources.
+
+## Specification
+
+[The ECMA-262 specification](https://www.ecma-international.org/publications/standards/Ecma-262.htm) contains the most in-depth, detailed and formalized information about JavaScript. It defines the language.
+
+But being that formalized, it's difficult to understand at first. So if you need the most trustworthy source of information about the language details, the specification is the right place. But it's not for everyday use.
+
+A new specification version is released every year. In-between these releases, the latest specification draft is at <https://tc39.es/ecma262/>.
+
+To read about new bleeding-edge features, including those that are "almost standard" (so-called "stage 3"), see proposals at <https://github.com/tc39/proposals>.
+
+Also, if you're in developing for the browser, then there are other specs covered in the [second part](info:browser-environment) of the tutorial.
+
+## Manuals
+
+- **MDN (Mozilla) JavaScript Reference** is a manual with examples and other information. It's great to get in-depth information about individual language functions, methods etc.
+
+    One can find it at <https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference>.
+
+    Although, it's often best to use an internet search instead. Just use "MDN [term]" in the query, e.g. <https://google.com/search?q=MDN+parseInt> to search for `parseInt` function.
+
+
+- **MSDN** – Microsoft manual with a lot of information, including JavaScript (often referred to as JScript). If one needs something specific to Internet Explorer, better go there: <http://msdn.microsoft.com/>.
+
+    Also, we can use an internet search with phrases such as "RegExp MSDN" or "RegExp MSDN jscript".
+
+## Compatibility tables
+
+JavaScript is a developing language, new features get added regularly.
+
+To see their support among browser-based and other engines, see:
+
+- <http://caniuse.com> - per-feature tables of support, e.g. to see which engines support modern cryptography functions: <http://caniuse.com/#feat=cryptography>.
+- <https://kangax.github.io/compat-table> - a table with language features and engines that support those or don't support.
+
+All these resources are useful in real-life development, as they contain valuable information about language details, their support etc.
+
+Please remember them (or this page) for the cases when you need in-depth information about a particular feature.

1-js/01-getting-started/2-code-editors/article.md → 1-js/01-getting-started/3-code-editors/article.md

@@ -12,14 +12,12 @@ An IDE loads the project (which can be many files), allows navigation between fi
 
 If you haven't selected an IDE yet, consider the following options:
 
-- [WebStorm](http://www.jetbrains.com/webstorm/) for frontend development. The same company offers other editors for other languages (paid).
-- [Netbeans](http://netbeans.org/) (free).
+- [Visual Studio Code](https://code.visualstudio.com/) (cross-platform, free).
+- [WebStorm](http://www.jetbrains.com/webstorm/) (cross-platform, paid).
 
-All of these IDEs are cross-platform.
+For Windows, there's also "Visual Studio", not to be confused with "Visual Studio Code". "Visual Studio" is a paid and mighty Windows-only editor, well-suited for the .NET platform. It's also good at JavaScript. There's also a free version [Visual Studio Community](https://www.visualstudio.com/vs/community/).
 
-For Windows, there's also "Visual Studio", not to be confused with "Visual Studio Code." "Visual Studio" is a paid and mighty Windows-only editor, well-suited for the .NET platform. A free version of it is called [Visual Studio Community](https://www.visualstudio.com/vs/community/).
-
-Many IDEs are paid but have a trial period. Their cost is usually negligible compared to a qualified developer's salary, so just choose the best one for you.
+Many IDEs are paid, but have a trial period. Their cost is usually negligible compared to a qualified developer's salary, so just choose the best one for you.
 
 ## Lightweight editors
 
@@ -33,21 +31,12 @@ In practice, lightweight editors may have a lot of plugins including directory-l
 
 The following options deserve your attention:
 
-- [Visual Studio Code](https://code.visualstudio.com/) (cross-platform, free) also has many IDE-like features.
 - [Atom](https://atom.io/) (cross-platform, free).
+- [Visual Studio Code](https://code.visualstudio.com/) (cross-platform, free).
 - [Sublime Text](http://www.sublimetext.com) (cross-platform, shareware).
 - [Notepad++](https://notepad-plus-plus.org/) (Windows, free).
 - [Vim](http://www.vim.org/) and [Emacs](https://www.gnu.org/software/emacs/) are also cool if you know how to use them.
 
-## My favorites
-
-The personal preference of the author is to have both an IDE for projects and a lightweight editor for quick and easy file editing.
-
-I'm using:
-
-- As an IDE for JS -- [WebStorm](http://www.jetbrains.com/webstorm/) (I switch to one of the other JetBrains offerings when using other languages)
-- As a lightweight editor -- [Sublime Text](http://www.sublimetext.com) or [Atom](https://atom.io/).
-
 ## Let's not argue
 
 The editors in the lists above are those that either I or my friends whom I consider good developers have been using for a long time and are happy with.

1-js/01-getting-started/3-devtools/article.md → 1-js/01-getting-started/4-devtools/article.md

@@ -8,7 +8,7 @@ To see errors and get a lot of other useful information about scripts, "develope
 
 Most developers lean towards Chrome or Firefox for development because those browsers have the best developer tools. Other browsers also provide developer tools, sometimes with special features, but are usually playing "catch-up" to Chrome or Firefox. So most developers have a "favorite" browser and switch to others if a problem is browser-specific.
 
-Developer tools are potent; they have many features. To start, we'll learn how to open them, look at errors, and run JavaScript commands.
+Developer tools are potent, they have many features. To start, we'll learn how to open them, look at errors, and run JavaScript commands.
 
 ## Google Chrome
 
@@ -29,10 +29,15 @@ The exact look of developer tools depends on your version of Chrome. It changes
 - Here we can see the red-colored error message. In this case, the script contains an unknown "lalala" command.
 - On the right, there is a clickable link to the source `bug.html:12` with the line number where the error has occurred.
 
-Below the error message, there is a blue `>` symbol. It marks a "command line" where we can type JavaScript commands. Press `key:Enter` to run them (`key:Shift+Enter` to input multi-line commands).
+Below the error message, there is a blue `>` symbol. It marks a "command line" where we can type JavaScript commands. Press `key:Enter` to run them.
 
 Now we can see errors, and that's enough for a start. We'll come back to developer tools later and cover debugging more in-depth in the chapter <info:debugging-chrome>.
 
+```smart header="Multi-line input"
+Usually, when we put a line of code into the console, and then press `key:Enter`, it executes.
+
+To insert multiple lines, press `key:Shift+Enter`. This way one can enter long fragments of JavaScript code.
+```
 
 ## Firefox, Edge, and others
 
@@ -50,12 +55,6 @@ Open Preferences and go to the "Advanced" pane. There's a checkbox at the bottom
 
 Now `key:Cmd+Opt+C` can toggle the console. Also, note that the new top menu item named "Develop" has appeared. It has many commands and options.
 
-## Multi-line input
-
-Usually, when we put a line of code into the console, and then press `key:Enter`, it executes.
-
-To insert multiple lines, press `key:Shift+Enter`.
-
 ## Summary
 
 - Developer tools allow us to see errors, run commands, examine variables, and much more.

1-js/02-first-steps/01-hello-world/1-hello-alert/index.html

@@ -0,0 +1,12 @@
+<!DOCTYPE html>
+<html>
+
+<body>
+
+  <script>
+    alert( "I'm JavaScript!" );
+  </script>
+
+</body>
+
+</html>

1-js/02-first-steps/01-hello-world/1-hello-alert/solution.md

@@ -0,0 +1,2 @@
+
+[html src="index.html"]