swift--using the IS and as operators for type checking and conversion

Declare several classes:

// Animal Class class animal{    }// Terrestrial Animal class   terricole:animal {    }// Marine Animal Class class seaanimals:animal {    }

1,is used for type checking.

Let cat =terricole () Let fish=seaanimals () let arr=[Cat,fish] forAnimainchArr {ifAnima isterricole{Print ("It's a land animal .")            }Else ifAnima isseaanimals{Print ("This is a marine animal .")            }        }

2, as is used for type conversion (NOTE: If you are unsure whether the type conversion succeeds, you can add a question mark "?")

 for inch arr {            ifas? terricole{                print (" This is a land animal " )            }Elseif? seaanimals{                Print (" This is marine animal ")            }        

swift--using the IS and as operators for type checking and conversion