American National Standard for Information Systems – Programming Language REXX

 ANSI®
X3J18-199X

Скачать в формате PDF

Скачать в формате DOC

Скачать в формате PS

Здесь представлен национальный американский стандарт  по языку REXX.

Purpose
This standard provides an unambiguous definition of the programming language REXX. Its purpose is to facilitate portability of REXX programs for use on a wide variety of computer systems.
History
The computer programming language REXX was designed by Mike Cowlishaw to satisfy the following principal aims:
– to provide a highly readable command programming language for the benefit of programmers and program readers, users and maintainers;
– to incorporate within this language program design features such as natural data typing and control structures which would contribute to rapid, efficient and accurate program development;
– to define a language whose implementations could be both reliable and efficient on a wide variety of computing platforms.
However, it has become apparent that REXX has attributes that go far beyond these original goals. Given this retrospect, we would now add a fourth goal:
– to provide a programming language that is appropriate for a wide variety of uses of both systems and applications software.
REXX is being used increasingly in the commercial and educational sectors; this standard is primarily a consequence of the growing commercial interest in REXX and the need to promote the portability of REXX programs between data processing systems. In drafting this standard the continued stability of REXX has been a prime objective.
In June, 1990, a proposal to develop an X3 Standard for the REXX programming language was submitted to the X3 Secretariat/CBEMA. This proposal called for the establishment of a new X3 Technical Committee for REXX.
In November, 1990, X3 announced the formation of a new technical committee, X3J18, to develop an American National Standard for REXX. The first meeting of this committee as X3J18 was held in January, 1991.
Committee lists This standard was prepared by the Technical Development Committee for
REXX, X3J18.
There are two annexes in this standard. Both annexes are informative and are not considered part of this standard.
Suggestions for improvement of this standard will be welcome. They should be sent to the Information Technology Industry Council, 1250 Eye Street, NW, Washington
DC 20005-3922.
This standard was processed and approved for submittal to ANSI by the Accredited Standards Committee on Information Processing Systems, X3. Committee approval of this standard does not necessarily imply that all
committee members voted for its approval. At the time it approved this

0 Introduction
This standard provides an unambiguous definition of the programming language REXX.


1 Scope, purpose, and application
1.1 Scope
This standard specifies the semantics and syntax of the programming language REXX by specifying requirements for a conforming language processor. The scope of this standard includes
– the syntax and constraints of the REXX language;
– the semantic rules for interpreting REXX programs;
– the restrictions and limitations that a conforming language processor may impose;

– the semantics of configuration interfaces. This standard does not specify
– the mechanism by which REXX programs are transformed for use by a data-processing system;
– the mechanism by which REXX programs are invoked for use by a data-processing system;
– the mechanism by which input data are transformed for use by a REXX program;
– the mechanism by which output data are transformed after being produced by a REXX
program;
– the encoding of REXX programs;
– the encoding of data to be processed by REXX programs;
– the encoding of output produced by REXX programs;
– the size or complexity of a program and its data that will exceed the capacity of any specific data-processing system or the capacity of a particular language processor;
– all minimal requirements of a data-processing system that is capable of supporting a conforming language processor;
– the syntax of the configuration interfaces.


1.2 Purpose
The purpose of this standard is to facilitate portability of REXX programs for use on a wide variety of configurations.


1.3 Application
This standard is applicable to REXX language processors.


1.4 Recommendation
It is recommended that before detailed reading of this standard, a reader should first be familiar with the REXX language, for example through reading one of the books about REXX. It is also recommended that Annex A and Annex B should be read in conjunction with this standard.


2 Normative references
There are no standards which constitute provisions of this American National Standard.