val T: Boolean = true
val F: Boolean = false

T || F                      // true
T && (T && F)               // false
!T                          // false
!(!T)                       // true

// equality
1 == 2                      // false
1 != 2                      // true

'''
Michael Sjoeberg
2018-11-05
https://github.com/michaelsjoeberg/scala-playground/blob/master/basic-syntax/logical-operators.scala
'''