Merge branch 'master' of https://github.com/iliakan/javascript-tutorial-en

Author: davegregg

1-js/02-first-steps/10-ifelse/4-check-login/solution.md

@@ -9,13 +9,13 @@ if (userName == 'Admin') {
 
   if (pass == 'TheMaster') {
     alert( 'Welcome!' );
-  } else if (pass == null) {
+  } else if (pass == '' || pass == null) {
     alert( 'Canceled.' );
   } else {
     alert( 'Wrong password' );
   }
 
-} else if (userName == null) {
+} else if (userName == '' || userName == null) {
   alert( 'Canceled' );
 } else {
   alert( "I don't know you" );

1-js/02-first-steps/10-ifelse/4-check-login/task.md

@@ -20,4 +20,6 @@ The schema:
 
 Please use nested `if` blocks. Mind the overall readability of the code.
 
+Hint: passing an empty input to a prompt returns an empty string `''`. Pressing `key:ESC` during a prompt returns `null`.
+
 [demo]

1-js/02-first-steps/10-ifelse/article.md

@@ -188,7 +188,7 @@ The same logic using `if..else`:
 ```js
 if (age < 3) {
   message = 'Hi, baby!';
-} else if (a < 18) {
+} else if (age < 18) {
   message = 'Hello!';
 } else if (age < 100) {
   message = 'Greetings!';

1-js/04-object-basics/01-object/article.md

@@ -83,7 +83,6 @@ let user = {
 ![](object-user-props.png)
 
 
-````smart header="Trailing comma"
 The last property in the list may end with a comma:
 ```js
 let user = {
@@ -92,7 +91,6 @@ let user = {
 }
 ```
 That is called a "trailing" or "hanging" comma. Makes it easier to add/remove/move around properties, because all lines become alike.
-````
 
 ## Square brackets
 
@@ -226,7 +224,7 @@ That can become a source of bugs and even vulnerabilies if we intent to store ar
 
 In that case the visitor may choose "__proto__" as the key, and the assignment logic will be ruined (as shown above).
 
-There exist a way to make objects treat `__proto__` as a regular property, we'll cover it later, but first we need to know more about objects to understand it. 
+There is a way to make objects treat `__proto__` as a regular property, which we'll cover later, but first we need to know more about objects. 
 There's also another data structure [Map](info:map-set-weakmap-weakset), that we'll learn in the chapter <info:map-set-weakmap-weakset>, which supports arbitrary keys.
 ````
 
@@ -370,7 +368,7 @@ Also, we could use another variable name here instead of `key`. For instance, `"
 
 ### Ordered like an object
 
-Are objects ordered? In other words, if we loop over an object, do we get all properties in the same order that they are added in it? Can we rely on it?
+Are objects ordered? In other words, if we loop over an object, do we get all properties in the same order they were added? Can we rely on this?
 
 The short answer is: "ordered in a special fashion": integer properties are sorted, others appear in creation order. The details follow.
 
@@ -514,7 +512,7 @@ admin.name = 'Pete'; // changed by the "admin" reference
 alert(*!*user.name*/!*); // 'Pete', changes are seen from the "user" reference
 ```
 
-The example above demonstrates that there is only one object. Like if we had a cabinet with two keys and used one of them (`admin`) to get into it. Then, if we later use the other key (`user`) we would see changes.
+The example above demonstrates that there is only one object. As if we had a cabinet with two keys and used one of them (`admin`) to get into it. Then, if we later use the other key (`user`) we would see changes.
 
 ### Comparison by reference
 
@@ -541,7 +539,7 @@ let b = {}; // two independent objects
 alert( a == b ); // false
 ```
 
-For comparisons like `obj1 > obj2` or for a comparison against a primitive `obj == 5`, objects are converted to primitives. We'll study how object conversions work very soon, but to say the truth, such comparisons are necessary very rarely and usually are a result of a coding mistake.
+For comparisons like `obj1 > obj2` or for a comparison against a primitive `obj == 5`, objects are converted to primitives. We'll study how object conversions work very soon, but to tell the truth, such comparisons are necessary very rarely and usually are a result of a coding mistake.
 
 ### Const object
 
@@ -739,4 +737,4 @@ There are many other kinds of objects in JavaScript:
 
 They have their special features that we'll study later. Sometimes people say something like "Array type" or "Date type", but formally they are not types of their own, but belong to a single "object" data type. And they extend it in various ways.
 
-Objects in JavaScript are very powerful. Here we've just scratched the surface of the topic that is really huge. We'll be closely working with objects and learning more about them in further parts of the tutorial.
+Objects in JavaScript are very powerful. Here we've just scratched the surface of a topic that is really huge. We'll be closely working with objects and learning more about them in further parts of the tutorial.

1-js/05-data-types/07-map-set-weakmap-weakset/article.md

@@ -138,7 +138,7 @@ let recipeMap = new Map([
 
 // iterate over keys (vegetables)
 for (let vegetable of recipeMap.keys()) {
-  alert(vegetable); // cucumber, tomateos, onion
+  alert(vegetable); // cucumber, tomatoes, onion
 }
 
 // iterate over values (amounts)

1-js/06-advanced-functions/11-currying-partials/article.md

@@ -95,7 +95,7 @@ user.sayNow = partial(user.say, new Date().getHours() + ':' + new Date().getMinu
 
 user.sayNow("Hello");
 // Something like:
-// [10:00] Hello, John!
+// [10:00] John: Hello!
 ```
 
 The result of `partial(func[, arg1, arg2...])` call is a wrapper `(*)` that calls `func` with:

1-js/07-object-oriented-programming/02-property-accessors/article.md

@@ -128,7 +128,7 @@ Object.defineProperty(user, 'fullName', {
 
 alert(user.fullName); // John Smith
 
-for(let key in user) alert(key);
+for(let key in user) alert(key); // name, surname
 ```
 
 Please note once again that a property can be either an accessor or a data property, not both.

1-js/08-error-handling/1-try-catch/article.md

@@ -295,7 +295,7 @@ try {
 
 As we can see, that's a `SyntaxError`.
 
-And in our case, the absense of `name` could be treated as a syntax error also, assuming that users must have a `name`.
+And in our case, the absence of `name` could be treated as a syntax error also, assuming that users must have a `name`.
 
 So let's throw it:
 

2-ui/1-document/01-browser-environment/article.md

@@ -80,8 +80,8 @@ Browser Object Model (BOM) are additional objects provided by the browser (host
 
 For instance:
 
-- [navigator](mdn:api/Window/navigator) object provides background information about the browser and the operating system. There are many properties, but the two most widely known are: `navigator.userAgent` -- about the current browser, and `navigator.platform` -- about the platform (can help to differ between Windows/Linux/Mac etc).
-- [location](mdn:api/Window/location) object allows us to read the current URL and can redirect the browser to a new one.
+- The [navigator](mdn:api/Window/navigator) object provides background information about the browser and the operating system. There are many properties, but the two most widely known are: `navigator.userAgent` -- about the current browser, and `navigator.platform` -- about the platform (can help to differ between Windows/Linux/Mac etc).
+- The [location](mdn:api/Window/location) object allows us to read the current URL and can redirect the browser to a new one.
 
 Here's how we can use the `location` object:
 
@@ -112,7 +112,7 @@ CSSOM specification
 : Describes stylesheets and style rules, manipulations with them and their binding to documents, see <https://www.w3.org/TR/cssom-1/>.
 
 HTML specification
-: Describes HTML language (tags etc.) and also BOM (browser object model) -- various browser functions: `setTimeout`, `alert`, `location` and so on, see <https://html.spec.whatwg.org>. It takes DOM specification and extends it with many additional properties and methods.
+: Describes the HTML language (e.g. tags) and also the BOM (browser object model) -- various browser functions: `setTimeout`, `alert`, `location` and so on, see <https://html.spec.whatwg.org>. It takes the DOM specification and extends it with many additional properties and methods.
 
 Now we'll get down to learning DOM, because the document plays the central role in the UI.
 

2-ui/1-document/05-basic-dom-node-properties/2-lastchild-nodetype-inline/task.md

@@ -4,7 +4,7 @@ importance: 5
 
 # What's in the nodeType?
 
-What the script shows?
+What does the script show?
 
 ```html
 <html>