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iOS Swift Collections and Control Flow Control Flow With Conditional Statements Logical Operators

Miguel Garcia
Miguel Garcia
1,002 Points
Posted by Miguel Garcia
Miguel Garcia
1,002 Points

Question of the AND Operator

What result gives us the AND Operator if the statement is "False && False"? The whole expression is still False?

1 Answer

Joe Beltramo
Joe Beltramo
Courses Plus Student 22,191 Points

AND operators are short circuits for checking if the first value is false. If the first value is false, there is no reason for the language to continue parsing the rest of the statement as the rest of it no longer matters.

OR operators are short circuits for checking if the first value is true. If the first value is true, the rest of the statements can be ignored as the criteria has already been satisfied.

so:

let everythingStopsHere = false
let noneOfThisMatters = false

if everythingStopsHere && noneOfThisMatters {
   // This is not entered, no code in here will be executed
}

// everythingStopsHere is the only part that was processed

let thisIsProcessed = true
let notProcessed = false

if thisIsProcessed || notProcessed {
  // thisIsProcessed is the only part that was processed because it was true, so notProcessed was ignored
}