more on js

docs/javascript.md

@@ -1,75 +1,15 @@
 # JavaScript
 
-You can write micro:bit programs in a subset of [TypeScript](https://www.typescriptlang.org), a superset of JavaScript.
+If you already know some JavaScript, you might be interested in [the JavaScript and TypeScript languages](/js/lang).
-Many micro:bit programs, especially at the beginner's level, are just plain JavaScript. TypeScript introduces class-based 
+Otherwise, visit the cards below to starting programming JavaScript with the micro:bit:
-object-oriented programming, such as:
 
-```typescript
+```codecard
-class Greeter {
+[{
-    greeting: string;
+  "name": "Calling Functions",
-    constructor(message: string) {
+  "url":"/js/call.md"
-        this.greeting = message;
+},{
+  "name": "Sequencing Commands",
+  "url":"/js/sequence.md"
 }
-    greet() {
+]
-        return "Hello, " + this.greeting;
-    }
-}
-
-let greeter = new Greeter("world");
-basic.showString(greeter.greet())
 ```
-
-This site is meant for teaching programming first, and JavaScript second. For this
-reason, we have stayed away from concepts that are specific to JavaScript (for
-example, prototype inheritance), and instead focused on ones common to most
-modern programming languages (for example, loops, lexically scoped variables,
-functions, classes, lambdas).
-
-We leverage TypeScript's [type inference](http://www.typescriptlang.org/docs/handbook/type-inference.html) so that
-students need not specify types when clear from context.
-
-## Supported language features
-
-* top-level code in the file: "Hello world!" really is just `basic.showString("Hello world!")`
-* [basic types](http://www.typescriptlang.org/docs/handbook/basic-types.html)
-* [variable declarations](http://www.typescriptlang.org/docs/handbook/variable-declarations.html): `let`, `const`, and `var`
-* [functions](http://www.typescriptlang.org/docs/handbook/functions.html) with lexical scoping and recursion
-
-### User-defined types and modules
-
-* [classes](http://www.typescriptlang.org/docs/handbook/classes.html) with fields, methods and constructors; `new` keyword
-* [enums](http://www.typescriptlang.org/docs/handbook/enums.html)
-* [namespaces](http://www.typescriptlang.org/docs/handbook/namespaces.html)  (a form of modules) 
-
-### Control-flow constructs
-
-* `if ... else if ... else` statements
-* `while` and `do ... while` loops
-* `for(;;)` loops (see below about `for ... in/of`)
-* `break/continue`; also with labeled loops
-* `switch` statement (on numbers only)
-* `debugger` statement for breakpoints
-
-### Expressions
-
-* conditional operator `? :`; lazy boolean operators
-* all arithmetic operators (including bitwise operators); note that in microcontroller targets
-  all arithmetic is performed on integers, also when simulating in the browser
-* strings (with a few common methods)
-* [string templates](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Template_literals) (`` `x is ${x}` ``)
-* arrow functions `() => ...`
-* array literals `[1, 2, 3]`
-
-
-## Unsupported language features
-
-We generally stay away from the more dynamic parts of JavaScript. 
-Things you may miss and we may implement:
-
-* exceptions (`throw`, `try ... catch`, `try ... finally`)
-* `for ... of` statements
-* object literals `{ foo: 1, bar: "two" }`
-* method-like properties (get/set accessors)
-* class inheritance
-
-If there is something you'd like to see, please file an issue at [GitHub](http://github.com/microsoft/pxt/issues).

docs/js/call.md

@@ -24,35 +24,18 @@ to select. You also narrow down the set of functions by typing, as below:
 
 You might have noticed that the call `showString` above takes one value, 
 the string to be scrolled on the LED screen. There is a second (optional)
-parameter that controls the speed of the the scroll. Try this:
+parameter that controls the speed of the scroll. Try this:
 
 ```typescript
 basic.showString("Hello!",50)
 ```
 
+If you don't give a value for an optional parameter, where does its value
+come from? TBD. 
+
 You might have noticed that the function list above shows all
 the available parameters for each function. 
 
-
+### ~button /js/sequence
-```typescript
+NEXT: Sequencing Commands
-basic.showString("Hello!")
+### ~
-basic.showLeds(`
-    . # . # .
-    . . . . .
-    . . # . .
-    # . . . #
-    . # # # .
-    `)
-basic.pause(1000)
-basic.clearScreen()
-basic.showString("Goodbye!")
-basic.showLeds(`
-    . # . # .
-    . . . . .
-    . . . . .
-    . # # # .
-    # . . . #
-    `)
-basic.pause(1000)
-basic.clearScreen()
-```

docs/js/lang.md

@@ -0,0 +1,75 @@
+# JavaScript and TypeScript
+
+You can write micro:bit programs in a subset of [TypeScript](https://www.typescriptlang.org), a superset of JavaScript.
+Many micro:bit programs, especially at the beginner's level, are just plain JavaScript. TypeScript introduces class-based 
+object-oriented programming, such as:
+
+```typescript
+class Greeter {
+    greeting: string;
+    constructor(message: string) {
+        this.greeting = message;
+    }
+    greet() {
+        return "Hello, " + this.greeting;
+    }
+}
+
+let greeter = new Greeter("world");
+basic.showString(greeter.greet())
+```
+
+This site is meant for teaching programming first, and JavaScript second. For this
+reason, we have stayed away from concepts that are specific to JavaScript (for
+example, prototype inheritance), and instead focused on ones common to most
+modern programming languages (for example, loops, lexically scoped variables,
+functions, classes, lambdas).
+
+We leverage TypeScript's [type inference](http://www.typescriptlang.org/docs/handbook/type-inference.html) so that
+students need not specify types when clear from context.
+
+## Supported language features
+
+* top-level code in the file: "Hello world!" really is just `basic.showString("Hello world!")`
+* [basic types](http://www.typescriptlang.org/docs/handbook/basic-types.html)
+* [variable declarations](http://www.typescriptlang.org/docs/handbook/variable-declarations.html): `let`, `const`, and `var`
+* [functions](http://www.typescriptlang.org/docs/handbook/functions.html) with lexical scoping and recursion
+
+### User-defined types and modules
+
+* [classes](http://www.typescriptlang.org/docs/handbook/classes.html) with fields, methods and constructors; `new` keyword
+* [enums](http://www.typescriptlang.org/docs/handbook/enums.html)
+* [namespaces](http://www.typescriptlang.org/docs/handbook/namespaces.html)  (a form of modules) 
+
+### Control-flow constructs
+
+* `if ... else if ... else` statements
+* `while` and `do ... while` loops
+* `for(;;)` loops (see below about `for ... in/of`)
+* `break/continue`; also with labeled loops
+* `switch` statement (on numbers only)
+* `debugger` statement for breakpoints
+
+### Expressions
+
+* conditional operator `? :`; lazy boolean operators
+* all arithmetic operators (including bitwise operators); note that in microcontroller targets
+  all arithmetic is performed on integers, also when simulating in the browser
+* strings (with a few common methods)
+* [string templates](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Template_literals) (`` `x is ${x}` ``)
+* arrow functions `() => ...`
+* array literals `[1, 2, 3]`
+
+
+## Unsupported language features
+
+We generally stay away from the more dynamic parts of JavaScript. 
+Things you may miss and we may implement:
+
+* exceptions (`throw`, `try ... catch`, `try ... finally`)
+* `for ... of` statements
+* object literals `{ foo: 1, bar: "two" }`
+* method-like properties (get/set accessors)
+* class inheritance
+
+If there is something you'd like to see, please file an issue at [GitHub](http://github.com/microsoft/pxt/issues).

docs/js/seqeunce.md

@@ -0,0 +1,23 @@
+## Sequencing commands
+
+By calling one function after another, you can create an animation:
+
+```typescript
+basic.showLeds(`
+    . # . # .
+    . . . . .
+    . . # . .
+    # . . . #
+    . # # # .
+    `)
+basic.showLeds(`
+    . # . # .
+    . . . . .
+    . . . . .
+    . # # # .
+    # . . . #
+    `)
+```
+
+## The Semicolon
+