Task

Determine whether a given year is a leap year in the Gregorian calendar.



See also

 Leap year (wiki)


  ( leap-year
  =   
    .     mod$(!arg.100):0
        & `(mod$(!arg.400):0) { The backtick skips the remainder of the OR operation,
                                even if the tested condition fails. }
      | mod$(!arg.4):0
  )
& 1600 1700 1899 1900 2000 2006 2012:?tests
&   whl
  ' ( !tests:%?test ?tests
    & ( leap-year$!test&out$(!test " is a leap year")
      | out$(!test " is not a leap year")
      )
    )
& ;