13.5 Case Ranges
You can specify a range of consecutive values in a single case label, like this:
case low ... high:
This has the same effect as the proper number of individual case labels,
one for each integer value from low
to
high
, inclusive. This is a non-standard extension to the language.
Using this feature reduces your code portability.
This feature is especially useful for ranges of ASCII character codes:
case 'A' ... 'Z':
Be careful: Write spaces around the..., otherwise it may be parsed incorrectly when you use it with integer values. For example, write this:
case 1 ... 5:
rather than this:
case 1...5: