Ada Lab Examples

Fifteen runnable Ada programs that follow the track's lesson order, grouped by phase. Every file is self-contained and fully commented. Compile them with GNAT (gnatmake file.adb — see the run notes at the bottom) or open them in the code viewer and change one thing, then compile again. That second run is where the learning happens.

Foundations

Hello world and the typed declaration discipline — the two files every later demo assumes you have seen.

#	Description	Link
1	Hello Ada — main procedure, context clause, Put_Line	View
2	Types and ranges — new types, subtypes, Constraint_Error	View

Basic Constructs

Selection, repetition, text, and enumerations — the everyday logic vocabulary.

#	Description	Link
3	Conditionals — if/elsif and a compiler-checked case	View
4	Loops — for, reverse, while, loop/exit, labels	View
5	Strings — fixed, slices, unbounded growth	View
6	Enumerations — attributes, case coverage, representation	View

Data & Logic

Arrays, records with variants, safe references, and decomposition into subprograms.

#	Description	Link
7	Arrays — aggregates, slices, enum-indexed arrays	View
8	Records — nesting, variant discriminants, defaults	View
9	Access types — allocation, dereference, null safety	View
10	Subprograms — modes, overloading, expression functions	View

Modular Systems

The first multi-file demos: a package with a private type, exception flow, and a generic container.

#	Description	Link
11	Package spec (geometry.ads) — private type + API	View
12	Package body (geometry.adb) — the implementation	View
13	Client of the package + exception handling	View
14	Exceptions — raise, propagate, messages	View
15	Generics — a generic stack, instantiated twice	View

Advanced Paradigms

Tagged dispatch, contracts, concurrency, and the standard containers.

#	Description	Link
16	OOP — tagged types, overriding, class-wide dispatch	View
17	Contracts — pre/postconditions and predicates	View
18	Tasking — tasks, protected bounded buffer	View
19	Standard library — Ada.Containers.Vectors and maps	View

How to run them. Compile straight from the demo folder: gnatmake demo/foundations/01_hello.adb then ./01_hello. The multi-file package pair compiles together: gnatmake demo/modular/12_package_main.adb (GNAT finds the spec and body automatically). Demos 3–14 need only GNAT; 17's delays make the interleaving visible; 18 needs any GNAT with the standard library. Larger multi-file study projects are on the Study Projects page.