Ada. Time-tested, safe and secure.

The title given to this book is incorrect due to technical limitations. The correct title is Ada Programming/Delimiters/...

The delimiter .. is used to specify ranges in any scalar type.

For example:

• In numeric type definitions:

type Count is range 0 .. Max_Count;

• In subtype definitions:

subtype Week_Day is Day_Name range Monday .. Friday;

• In variable declarations:

Vector_A : Vector (0 .. 31);

• In membership tests:

exit when X in Y .. Y + Epsilon;

• In for loops:

for Day in Day_Name range Monday .. Thursday loop
   -- ...
end loop;

• In arrays:

Vector_A (Vector_A'First .. Vector_A'First + Vector_B'Length - 1) := Vector_B;

Usage notes

When a whole type range will be specified, it is better to use the Range attribute.

For example, instead of using:

for Day in range Day_Name'First .. Day_Name'Last loop
   -- ...
end loop;

it is better to use:

for Day in Day_Name'Range loop
   -- ...
end loop;

See also