Ada Reference Manual (Ada 2022)

1.1.2 Structure

This document contains thirteen clauses, fifteen annexes, and an index.

The core of the Ada language consists of:

Clauses 1 through 13

Annex A, “Predefined Language Environment”

Annex B, “Interface to Other Languages”

Annex J, “Obsolescent Features”

The following Specialized Needs Annexes define features that are needed by certain application areas:

Annex C, “Systems Programming”

Annex D, “Real-Time Systems”

Annex E, “Distributed Systems”

Annex F, “Information Systems”

Annex G, “Numerics”

Annex H, “High Integrity Systems”

The core language and the Specialized Needs Annexes are normative, except that the material in each of the items listed below is informative:

Text under a NOTES or Examples heading.

Each subclause whose title starts with the word “Example” or “Examples”.

All implementations shall conform to the core language. In addition, an implementation may conform separately to one or more Specialized Needs Annexes.

The following Annexes are informative:

Annex K, “Language-Defined Aspects and Attributes”

Annex L, “Language-Defined Pragmas”

Annex M, “Summary of Documentation Requirements”

Annex N, “Glossary”

Annex P, “Syntax Summary”

Annex Q, “Language-Defined Entities”

Each clause is divided into subclauses that have a common structure. Each clause and subclause first introduces its subject. After the introductory text, text is labeled with the following headings:

Syntax

Syntax rules (indented).

Name Resolution Rules

Compile-time rules that are used in name resolution, including overload resolution.

Legality Rules

Rules that are enforced at compile time. A construct is legal if it obeys all of the Legality Rules.

Static Semantics

A definition of the compile-time effect of each construct.

Post-Compilation Rules

Rules that are enforced before running a partition. A partition is legal if its compilation units are legal and it obeys all of the Post-Compilation Rules.

Dynamic Semantics

A definition of the run-time effect of each construct.

Bounded (Run-Time) Errors

Situations that result in bounded (run-time) errors (see 1.1.5).

Erroneous Execution

Situations that result in erroneous execution (see 1.1.5).

Implementation Requirements

Additional requirements for conforming implementations.

Documentation Requirements

Documentation requirements for conforming implementations.

Metrics

Metrics that are specified for the time/space properties of the execution of certain language constructs.

Implementation Permissions

Additional permissions given to the implementer.

Implementation Advice

Optional advice given to the implementer. The word “should” is used to indicate that the advice is a recommendation, not a requirement. It is implementation defined whether or not a given recommendation is obeyed.

NOTE Notes emphasize consequences of the rules described in the (sub)clause or elsewhere. This material is informative.

Examples

Examples illustrate the possible forms of the constructs described. This material is informative.