JavaScript: converting values to boolean or what is false and what is true
What will !x
return? And !!x
? It depends on what is x
…
!x
will convert any value to a boolean, and !!x
will negate the previous value. When x
is a boolean, !x
is its negation and !!x
is back the original value x
. But for other types, some magic happens thanks to auto conversion.
What exactly? I’ll explain in several cases. JavaScript recognizes 7 primitive data types, of which the most prominent ones are:
…