02. Falsy and Truthy Values

It can be confusing to tell which values per data type evaluate to false or true. Let's go over them really quick.

Falsy values

Falsy values include the following:

var count;                   // no value assigned
count = false;               // boolean false
count = 0;                   // zero
count = '';                  // empty value
count = 10/'hello world!'    // NaN

Truthy Values

Truthy values include the following.

var highscore = true; // true boolean 
count = 1;            // numbers other than 0
count = 'carrot';     // non-empty string
count = 100/20;       // valid number
count = 'true';       // the string true
count = '0';          // any strings
count = 'false';      // 'false' the word as a string - non-empty

Short-circuiting values

If a value does not exist, it will evaluate to FALSE. We can take advantage of this with an OR statement

var name = 'Steven Hays';
var cadaver = (name || 'John Doe');

In this case, the cadaver will be assigned a name if it has one; otherwise, it'll be given the generic name John Doe.

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