Sometimes, you want to declare a subtype for a subset of the possible values of a private type. You might for example want a subtype of Ada.Calendar.Time, which only can include times in the past. If Ada.Calendar.Time was a numeric type, we could declare a subset …

There is every now and then need for viewing the file contents as "raw" bytes shown as hex numbers. Usually, operating systems have tool 'hexdump' to do this. But it is not hard to create one from scratch. Here is one example how to create a simple hexdump utility in …

There are some cases when you want to create and use multiple instances of same package. This is easily done by creating a generic package which does not take any parameters: generic package Counter is function Get_Number return Natural; end Counter; package body Counter is Counter_Value : Natural := 0; function Get_Number …

One may in some cases want an object to contain a reference ('Access) to itself. The package Self_Referencing_Objects shows how one can implement (consistently) self-referencing objects using limited records and discriminants. type Instance is limited private; ... type Holder (Reference : access Instance) is limited null record; type Instance is limited record …

Sometimes, you want to return different data from a function dependending on the given parameters and the program state. For example, when searching a container for a certain element, you either want to return "NOT_FOUND" information or the actual element. One way to do this is to use discriminated (or …

Have you ever struggled to create bindings for C types like FILE or CURL? If yes, then you know how hard it can be, since the type might not be same on all platforms. Easy solution for these is to define a null record which represents the type and use …

One, probably not so often used, feature of Ada.Text_IO is an ability to redirect output (Put, Put_Line, Newline) to a file. It happens simply by opening a file where you want to redirect the output and then calling Set_Output procedure. Example below shows how it is done: with Ada …

Open a web page on Windows using Ada