|
|
|
|
## Hello There 👋
|
|
|
|
|
|
|
|
|
|
### Values
|
|
|
|
|
|
|
|
|
|
There are 3 types of values, and they can model the **WORLD** !\
|
|
|
|
|
_(In the end it's all `1`'s and `0`'s for the computer)_, but us, **humans**, need
|
|
|
|
|
an easier way of representing stuff.
|
|
|
|
|
|
|
|
|
|
> We can all agree that `11010001100101110110011011001101111` is not a very
|
|
|
|
|
> friendly way to say `'hello'` !
|
|
|
|
|
|
|
|
|
|
#### Numbers 🔢
|
|
|
|
|
|
|
|
|
|
- Whole numbers: `1`, `23`, `232139283`
|
|
|
|
|
- Negative numbers are prefixed with `-`: `-1`, `-1231`
|
|
|
|
|
- Decimal numbers: `3.14`, `-2.53343` etc...
|
|
|
|
|
|
|
|
|
|
Use them for _quantities_ like in daily life.
|
|
|
|
|
|
|
|
|
|
#### Booleans ✖️ / ✔️
|
|
|
|
|
|
|
|
|
|
We use them when something is either `true` or `false`.
|
|
|
|
|
|
|
|
|
|
They can be used to represent an answer to a closed-ended question _(anything that can
|
|
|
|
|
be answered with yes or no)_.
|
|
|
|
|
|
|
|
|
|
> We would answer the question *Is your screen turned on ?*
|
|
|
|
|
> with the value `true` _(most likely)_.
|
|
|
|
|
|
|
|
|
|
#### Strings 🆒
|
|
|
|
|
|
|
|
|
|
- `'Hello'`
|
|
|
|
|
- `'This is some text'`
|
|
|
|
|
|
|
|
|
|
A string is a sequence of characters used to represent text, it needs
|
|
|
|
|
**delimiters** to define its _begining_ and _end_.\
|
|
|
|
|
Delimiters are matching quotes, either `` ` ``, `"` or `'`.
|
|
|
|
|
|
|
|
|
|
### Using `console.log`
|
|
|
|
|
|
|
|
|
|
To display output from a script into a console, use the function `console.log`:
|
|
|
|
|
|
|
|
|
|
```js
|
|
|
|
|
console.log() // <- will show an empty line
|
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
Add any value between the parentheses to see it appear when the script is
|
|
|
|
|
executed.
|
|
|
|
|
|
|
|
|
|
> It is very important to use this often to validate that our code is valid. The
|
|
|
|
|
> more it is tested, the easier it is to understand what's going on in the code
|
|
|
|
|
> !
|
|
|
|
|
>
|
|
|
|
|
> In doubt, `console.log` everything, don't be shy, they are for free.
|
|
|
|
|
|
|
|
|
|
### Instructions
|
|
|
|
|
|
|
|
|
|
In the editor block, write a program that displays:
|
|
|
|
|
|
|
|
|
|
- the exact text `Hello There !`
|
|
|
|
|
- any `Number`
|
|
|
|
|
- and a `Boolean`.
|
|
|
|
|
|
|
|
|
|
### Recommendation
|
|
|
|
|
|
|
|
|
|
Videos designed to give **hints** are assigned to each quest. It is strongly suggested to watch them as you go.
|
|
|
|
|
|
|
|
|
|
### You will learn about
|
|
|
|
|
|
|
|
|
|
- JavaScript primitive values
|