Remember: operator == is symmetric (if A == B then B == A)
but not transitive (A == B and B == C do not imply A == C)
!!(..) ? [if(...)]
!(..) ? [if(!...)]
== null ?
=== null ?
== undefined ?
=== undefined ?
== 0 ?
=== 0 ?
== '0' ?
=== '0' ?
== '' ?
=== '' ?
== [] ?
=== [] ?
== {} ?
=== {} ?
== NaN ?
=== NaN ?
== true ?
=== true ?
== false ?
=== false ?