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iOS Swift Functions and Optionals Optionals Optional Chaining

Alex Atwater
Alex Atwater
2,624 Points
Posted by Alex Atwater
Alex Atwater
2,624 Points

What’s the difference between doing findApt(“”)?.toInt() and findApt(“”)!.toInt() Seems to do same thing...

They Seem to do same thing and not throw an error in playground

1 Answer

Nicolo Figiani
Nicolo Figiani
4,012 Points
Nicolo Figiani
Nicolo Figiani
4,012 Points

  • findApt(“”)!.toInt() will work only if the findApt() functions returns a valid value. If this function returns a nil value, the "bang notation" (!) will give you an error.

  • instead, findApt(“”)?.toInt(), associated with an if-let statement, will unwrap the optional safely every time, wether the findApt(“”) function returns a valid value or a nil.