The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Subprograms and packages can be generic. Generic program units are templates of program units and are often parameterized. Being templates, they cannot be used directly as ordinary subprograms or packages; for example a generic subprogram cannot be called. Instances (that is, copies) of the template are obtained by generic instantiation. The resulting subprograms and packages are ordinary program...
Representation specifications specify how the types of the language are to be mapped onto the underlying machine. Mappings acceptable to an implementation do not alter the net effect of a program. They can be provided to give more efficient representation or to interface with features that are outside the domain of the language (for example, peripheral hardware).
The rules defining the scope of declarations and the rules defining which identifiers are visible at various points in the text of the program are described in this chapter. These rules are stated here as applying to identifiers. They apply equally to character strings used as function designators and to character literals used as enumeration literals.
The overall structure of programs and the facilities for separate compilation are described in this chapter. A program is a collection of one or more compilation units submitted to a compiler in one or more compilations. A compilation unit can be a subprogram declaration or body, a package declaration or body, a generic declaration, or a subunit, that is, the body of a subprogram, package, or task...
This report describes the programming language Ada, designed in accordance with the Steelman requirements of the United States Department of Defense. Overall, the Steelman requirements call for a language with considerable expressive power covering a wide application domain. As a result the language includes facilities offered by classical languages such as Pascal as well as facilities often found...
Packages allow the specification of groups of logically related entities. In their simplest form packages can represent pools of common data and type declarations. More generally, packages can be used to describe groups of related entities such as types, objects, and subprograms, whose inner workings are concealed and protected from their users.
Names can denote declared entities. These are objects, numbers, types and subtypes, subprograms, packages, tasks and their entries, and exceptions. Names can also be labels, block names, or loop names. Particular forms of names denote attributes, operators, and components of objects. Finally, a name can denote the result returned by a function call.
This chapter defines the facilities for dealing with errors or other exceptional situations that arise during program execution. An exception is an event that causes suspension of normal program execution. Drawing attention to the event is called raising the exception. Executing some actions, in response to the occurrence of an exception, is called handling the exception.
A subprogram is an executable program unit that is invoked by a subprogram call. Its definition can be given in two parts: a subprogram declaration defining its calling convention, and a subprogram body defining its execution. There are two forms of subprograms: procedures and functions. A procedure call is a statement; a function call returns a value.
Input-output facilities are predefined in the language by means of two packages. The generic package INPUT_OUTPUT defines a set of input-output primitives applicable to files containing elements of a single type. Additional primitives for text input-output are supplied in the package TEXT_IO. These facilities are described here, together with the conventions to be used for dealing with low level input-output...
In this report we present an implementation of a new method for the solution of convex programming problems based on the use of a homotopy path leading to an optimal solution through analytic centers. With a number of numerical test results on linear programming problems we indicate that this method has a favorable convergence behaviour and a substantial acceleration can be achieved by using a suitable...
Tasks are entities that may operate in parallel. Parallel tasks may be implemented on multicomputers, multiprocessors, or with interleaved execution on a single processor. Tasks may have entries which may be called by other tasks. Synchronization is achieved by rendezvous between a task issuing an entry call and a task accepting the call. Entries are also the principal means of communication between...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.