Node:What and why, Next:Current version, Up:GNU Pascal

#### What and why?

The purpose of the GNU Pascal project is to produce a Pascal compiler (called GNU Pascal or GPC) which

- combines the clarity of Pascal with powerful tools suitable for real-life programming,
- supports both the Pascal standard and the Extended Pascal standard as defined by ISO, ANSI and IEEE (ISO 7185:1990, ISO/IEC 10206:1991, ANSI/IEEE 770X3.160-1989),
- supports other Pascal standards (UCSD Pascal, Borland Pascal, parts of Borland Delphi, Mac Pascal and Pascal-SC) in so far as this serves the goal of clarity and usability,
- may be distributed under GNU license conditions, and
- can generate code for and run on any computer for which the GNU C compiler can generate code and run on.

Pascal was originally designed for teaching. GNU Pascal provides a smooth way to proceed to challenging programming tasks without learning a completely different language.

The current release implements Standard Pascal (ISO 7185, levels 0 and 1), most of Extended Pascal (ISO 10206, aiming for full compliance), is highly compatible to Borland Pascal (version 7.0), has some features for compatibility to other compilers (such as VAX Pascal, Sun Pascal, Mac Pascal, Borland Delphi and Pascal-SC).

It provides a lot of useful GNU extensions not found in other Pascal compilers, e.g. to ease the interfacing with C and other languages in a portable way, and to work with files, directories, dates and more, mostly independent of the underlying operating system.

Included units provide support for regular expressions, arithmetic with integer, rational and real numbers of unlimited size, internationalization, inter-process communication, message digests and more. Demo programs show the usage of these units and of many compiler features.