Ada Conformity Assessment Authority      Home Conformity Assessment   Test Suite ARGAda Standard
Overview of Ada 2022
Jeff Cousins
Contents   Index   Search   Previous   Next 

3.9 Defaults for generic formal types

Defaults for generic formal types (AI12-0205) provides easier and more natural generic instantiation. It uses the reserved words or use (see RM 12.5). For example:
   type Item_Type is private;
   type Item_Count is range <> or use Natural;
                 --  New syntax using or use
   with function "=" (L, R : in Item_Type) return Boolean;
package Lists is
end Lists;
This allows the instantiator to be able to provide a type for the Item_Count, but it can simply be omitted in ordinary circumstances (in which case Natural would be used).

Contents   Index   Search   Previous   Next 
© 2021, 2022 Jeff Cousins