Specifications

Compilers, Interpreters, and Assemblers
7.3 Ada
• Ada defined exception handling to recover from error conditions. User-defined
exception handling is also available.
VAX
The DEC Ada Professional Development Option is available on OpenVMS VAX
systems and is licensed separately. This option provides smart recompilation and
program library file-block caching to increase productivity.♦
7.4 APL
The VAX APL interpreter provides a built-in editor, debugger, system
communications facility, and file system. It automatically reserves space for
variables, formats input and output statements, and manipulates rows and
columns of data without loops. It can call another VAX APL program and have
data returned as a result.
7.5 BASIC
Digital offers two highly compatible versions of BASIC, VAX BASIC for
developing BASIC programs on OpenVMS VAX and DEC BASIC for
developing BASIC programs on OpenVMS AXP. Both products support a
robust implementation of the BASIC language, containing most constructs
found in other traditional programming languages and access to common record
definitions stored in the CDD/Repository (formerly named the Common Data
Dictionary). Both products are fully supported by the OpenVMS operating system
environment, including access to all utilities, the ability to invoke the callable
system routines, and the ability to use object modules from other programming
languages.
VAX BASIC and DEC BASIC support the following extensions to the traditional
BASIC language:
• Multiple integer and floating-point data types, the packed decimal data type,
and user defined records
• Structured programming statements, such as SELECT/CASE, IF/THEN
/ELSE, FOR/WHILE/UNTIL loops, local (DEF) and external functions, and
alphanumeric labels
• Sequential, relative, and indexed I/O through RMS
• Structured error handling
• Support for the OpenVMS Debugger
• Lexical compiler directives
VAX
VAX BASIC also provides an environment/intrepreter as well as a package of
language statements for performing graphics operations.♦
7.6 BLISS-32
VAX BLISS-32 supports development of modular software according to structured
programming concepts by providing an advanced set of language features. It
provides access to most of the hardware features of a VAX system.
VAX BLISS-32 programs include the following features that allow programs to be
transported to other Digital computer systems:
• High-level language constructs can be transferred from one machine to
another with little or no alteration.
7–4