Unconstrained Arrays

We have only used constrained array types so far

• the size of array was specified in type declaration, when the range of index values was specified

Ada also provides unconstrained array types

• element type is specified in type declaration
• index type is specified in type declaration
• range of index values (ie size) is not specified in type declaration
• specify range of index values in variable  declarations

Examples:

    type int_u_array is array (INTEGER range <>) of INTEGER;

    small_int_array : int_u_array (1 .. 3);	-- just 3 items

    big_int_array   : int_u_array (1 .. 100);	-- 100 items

    type char_count is array (CHARACTER range <>) of INTEGER;

    subtype digit_count is char_count('0' .. '9');

    uc_counts : char_count ('A' .. 'Z');

    dig_counts : digit_count;

STRING is an unconstrained array type

    type STRING is array (POSITIVE range <>) of CHARACTER;