Ada Programming/Attributes/'Last

Ada. Time-tested, safe and secure.
Ada. Time-tested, safe and secure.

Description edit

X'Last, where X is any scalar subtype (for example integer, enumerated, real), is an attribute that represents the last value (upper bound) in the range of X.

A'Last, where A is an array, denotes the last index value. For more-dimensional arrays, A'Last(N) denotes the last index value of the Nth dimension (N must be static).

Example edit

type My_Enum is (Enum1, Enum2, Enum3);
type My_Int  is range -1 .. 5;
pragma Assert (My_Enum'Last = Enum3);  -- OK
pragma Assert (My_Int'Last  = 5);      -- OK
pragma Assert (My_Int'Last  = 4);      -- Wrong!

See also edit

Wikibook edit

Ada Reference Manual edit