To know the value of a function and use a proper boolean may conclude that it is easier to distinguish which one is not real to begin with.
Overview
let myVariable = 'I Exist!'; if (myVariable) { console.log(myVariable) } else { console.log('The variable does not exist.') }
- The code block in the
if
statement will run becausemyVariable
has a truthy value; even though the value ofmyVariable
is not explicitly the valuetrue
, when used in a boolean or conditional context, it evaluates totrue
because it has been assigned a non-falsy value. - So which values are falsy— or evaluate to
false
when checked as a condition? The list of falsy values includes:0
- Empty strings like
""
or''
-
null
which represent when there is no value at all -
undefined
which represent when a declared variable lacks a value -
NaN
, or Not a Number
Code Snippets
let username = ''; let defaultName; if (username) { defaultName = username; } else { defaultName = 'Stranger'; }
a11y myths
Accessibility can only be tested by disabled people
Well, usually disabled people are the best testers - they use assistive technologies full time. However, everyone can learn how to test websites for accessibility.
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