Octave is a high-level language, primarily intended for numerical computations. It provides a convenient command line interface for solving linear and nonlinear problems numerically, and for performing other numerical experiments. It may also be used as a batch-oriented language.
Oberon2 is a simple and safe object-oriented language created by N.Wirth, the author of Pascal and Modula2. It is statically strongly typed and has garbage collection. Most of good ideas incorporated in design of Java were in Oberon2 long before. OOC is an open source project to produce a family of optimizing Oberon2 compilers. The compiler with an ANSI C back-end, oo2c, is quite mature, and provides a complete and convenient Oberon2 development environment. It comes with a rather comprehensive standard library, Code Navigator, and an Emacs mode. It is easy to call C functions and libraries from Oberon2.
Parse::Yapp provides a set of modules and a frontend to generate Perl OO LALR(1) parsers. It can input clean yacc or bison grammars. The generated parsers are fast, being based, like yacc, on building Deterministic Finite Automata (DFA) and moving through a set of states using Deterministic Push Down Automata (DPDA) derived from the DFA to match the input stream tokens.
PentiumGCC is a branch of GCC (the GNU Compiler Collection, formerly known as gcc/egcs) especially designed to optimize for x86 compatible chips. Speed improvements of 2-30% are possible. MMX support for P-II is being worked on. Since PentiumGCC is distributed as a patch to GCC, you will need to get the source code for the main GCC distribution to compile PentiumGCC.
The Portable Forth Environment implements the ANSI Standard of the Forth programming language. It is fully written in C, and with gcc the virtual machine can be put into cpu registers. The newer development versions implement a set of modern features including modularization and multithreading. The terminal connection itself can be configured to work in an embedded environment.
Pike is an interpreted, object-oriented, dynamic programming language with a syntax similar to C. It includes a powerful modules system that, for instance, has image manipulation, database connectivity and advanced cryptography. It is simple to learn, does not require long compilation passes and has powerful built-in data types allowing simple and fast data manipulation.
PRECC eXtended is an infinite-lookahead higher-order compiler-compiler for languages with context-dependent grammars. The generated code is ANSI C and ANSI C++; the code will compile and run natively under either C or C++. Specification scripts are extended BNF, with both inherited and synthetic attributes allowed. Scripts can be compiled in separate modules and linked later. The technology is essentially LL(oo).
Production BASIC is an Open-Source, Multi-user Business Basic compiler/interpreter and run-time environment. This system is intended to be an alternative to commercially available systems, such as Basic/Four, Thoroughbred, and others that have evolved from the original Basic/Four system. It creates meta-code object modules, and uses a run-time interpreter under Linux. The system is under development, and assistance is being solicited.