The data type for plain language

// RULE 1: Must be between balanced quotes
typeof 'Javascript is awesome!'; // 'string'

// RULE 2: Escape special characters
'Can\'t beat Javascript so don\'t try';

// RULE 3: Can have numbers, symbols, ANYTHING
'Jenny\'s #: ($%@)867-5309';

// Indexed, starting at 0
'Dancing in the street'[0]; // "D"
 0123456789...

// Immutable 
'I hear, the secrets that...'
 0123456789...

// Iterable (can loop through)
for (var index = 0; index < 10; index++) {
  console.log('JavaScript'[index]);
} 

[2] = 'f';

// NOPE!!! 

// "J", "a", "v", "a", "S", "c", "r", "i", "p", "t"

// How many characters?
'Don\'t sweat the technique'.length; // 25

// Convert to uppercase
'dance, magic dance!'.toUpperCase; // 'DANCE, MAGIC DANCE'

// Where is the letter
'Borderline!'.indexOf('r'); // 2

// Search for other Javascript string methods
// Use them when possible

Just do all the stuff you do with numbers...

JavaScript Memory

563463456...

2357

45.3346636...

13

// Numbers are numbers
13, 2357, 5634634564356456

// Decimals too
45.33466362363

// Oh! Negative nums
-45324543

-45324543

// Javascript Numbers

// Mathmatical operations
> 21 + 7; // ???

> 3.14 + 5; // ???

> 3 * 5; // ???

> 15 / 3; // ???

> 15 % 9; // ???

JavaScript Memory

3 * 5

3.14 + 5

15 / 3

21 + 7

15 % 9

// Javascript Numbers

// Mathmatical operations
> 21 + 7; // ???

> 3.14 + 5; // ???

> 3 * 5; // ???

> 15 / 3; // ???

> 15 % 9; // ???

JavaScript Memory

15

8.4

5

28

6

// Javascript Numbers' "METHODS"

// Is this a number?
typeof 523454;      // ???

// 'STRINGIFY' this number
55.00.toString();  // ???
77.toString();     // ???
(99).toString();   // ???

// Numberify a 'STRINGIFIED'
Number('453');     // ???

JavaScript Memory

ERROR

55

"99"

"number"

453

// Javascript Numbers Methods

// When adding numbers
600 + '400'; // ???

// When using some methods
54.435345.toFixed(2); // ???

// Combining methods and operations
10 + 54.435.toFixed(2); // ???

// Just to be safe???
Number(10 + 54.435.toFixed(2)); // ???

JavaScript Memory

"1054.44"

"54.44"

Try it!

"600400"

JavaScript Memory

64.44

54.441

1054.44

True, False | Truthy <> Falsy

// No grey areas, evaluates explicitly to true or false

> true; // Stevie Wonder is a musical genius

> false; // Is water dry?

// Not explicitly true or false, "If I had to pick one"

// "Truthy" <> Drake is more pop music than anything
> true, 1+, 'string', {}, [];

// "Falsy" <> Preston's pants are too colorful
> false, 0, null, undefined, "", NaN; 

// Relative Equivalence

JavaScript Memory

false

true

true

// Is 4 equal to 4
> 4 === 4; // ???

// Is 4 not equal to 5
> 4 !== 5; // ???

// Is 4 greater than 5
> 4 > 5; // ???

JavaScript Memory

false

false

true

// Is this the correct data type?
> typeof 'B, BBoys and [B]Girls' 

// Is this the correct data type?
> typeof 'Love is a battlefield!' 

// Is this the correct data type?
> typeof function letsDance() {} 

=== "string";

=== "number";

=== "function";

JavaScript Memory

false

> // Write a function that returns true 
  // if 'Moose rocks dance floors' EVALUATES to true
  (function() {

    // If the condition fails return false
    return false;
  })() // ???

    // Check if 'Moose rocks dance floors' is EQUAL to TRUE
    if ('Moose rocks dance floors' === true) {

JavaScript Memory

false

       // if yes, break the function and return true
       return true;
    }

JavaScript Memory

true

> // Create function that asks a user who the 5 goat rappers are
  (function() {
    var isTheGoat = false;

  })();

    // Google it!
    var goat = prompt("Who are the 5 goat rappers?").toUpperCase();

JavaScript Memory

false

    // Check if the 'goat' is the correct answer
    if (goat === 'DYLAN') {      
      // Is the goat?
      isTheGoat = true;

      // if correct, tell us who
      for (var i = 0; i < 5; i++) { alert(goat + '!') };
      

      // Then tell us why
      setTimeout(function() {alert('BECAUSE I SPIT HOT FIRE!')}, 2000);
      
     

      // Break out of the function and tell us the 'truth' 
      return isTheGoat; // OPTIONAL    
    }

    return isTheGoat; // true or false no matter what
  

JavaScript Memory

>// Does Moose rock dance floors?
 if ('Moose rocks dance floors!!!') {
    
    
    
  
 } // ???

JavaScript CONSOLE

    // If yes, print true
    console.log(true);

undefined

true

Absolute Equivalence

• true | false

Relative Equivalence

'falsy':

'truthy':