Black & White Series
Literals, Variables, and Constants
JavaScript for C or Java Programmers
Atomic Literals
type | typical values | |
---|---|---|
boolean | true | false |
number | 15 | 7.82 |
Strings
Basic string - two interchangeable options:
'basic string'
"basic string"
One can use one inside the other:
console.log('The dinosaur "jumped into the mud"')
Output:
The dinosaur "jumped into the mud"
Multiline String
`line 1
line 2
...`
Example:
console.log(`The dinosaur
jumped into the mud`)
Output:
The dinosaur
jumped into the mud
Automatic/Manual Conversions
console.log('2' + 3)
console.log(parseInt('2') + 3)
console.log('2' * 3)
console.log('x' - 3)
Automatic/Manual Conversions
console.log('2' + 3)
console.log(parseInt('2') + 3)
console.log('2' * 3)
console.log('x' - 3)
23
5
6
nan
NaN
- usual output for wrong expressions
Variable/Constant Declaration
<let/const/var> <name1> = <init1>,..., <namen> = <initn>
let
- a variable in a scope- equivalent behavior to C variables
const
- a constant in a scopevar
- old fashion variable declaration- rules for scope different from
let
-
not recommended in general
- rules for scope different from
Example
let price = 20, fees = 5
const pi = 3.1416
price += fee // right
pi = 3.14 // error
References
-
Mozilla MDN - https://developer.mozilla.org
-
Eloquent JavaScript - https://eloquentjavascript.net/
André Santanchè
www.ic.unicamp.br/~santanch/
Web2Learn
santanche.github.io/web2learn/