Range Operators

Swift 4 supports several types of range operators which are used as shorthand for expressing a range of values.

• Closed Range Operators
• Half-Open Range Operator
• One Sided Ranges

Closed Range Operator

The closed range operator (a...b) specifies the range between a and b (here a and b inclusive and value of a should not be greater than value of b). The closed range operator is useful when you have to iterate over a range in which you want all of the values to be used, such as with a for-in loop.

Example:

Output:

1 times 5 is 5
2 times 5 is 10
3 times 5 is 15
4 times 5 is 20
5 times 5 is 25
6 times 5 is 30
7 times 5 is 35
8 times 5 is 40
9 times 5 is 45
10 times 5 is 50

Half-Open Range Operator

The half-open range operator (a..<b) specifies a range between a to b, but it doesn?t include b. It is called half-open range operator because it contains its first value, but not its final value. Similarly as closed range operator, the value of a must not be greater than b in half-open range operator also. If the value of a is equal to b, then the resulting range will be empty.

Half-open range operator is generally used with arrays where it counts the length of the list.

Example:

Output:

Person 1 name is Albert
Person 2 name is Aryan
Person 3 name is Ajeet
Person 4 name is Jill

One Sided Ranges

One sided ranges operator is an alternative form of closed range operator or half-open range operator in one direction only.

Example1:

Output:

Ajeet
Jill

Example2:

Output:

Albert
Aryan
Ajeet

Example3:

Output:

Albert
Aryan