Xcerpt is a declarative, rule-based query and transformation language for XML, inspired by logic programming. Instead of the path-based navigational approach taken by languages like XSLT and XQuery, Xcerpt uses pattern-based, positional queries, where a pattern is an "example" of the database containing variables for binding content. As in logic programming, rules may be chained to form more complex queries.
Darcs is an advanced revision control system. It has two particularly distinctive features which differ from other revision control systems: each copy of the source is a fully functional branch, and underlying it is a consistent and powerful theory of patches. In spite of its power, darcs is simple to use, in part because of the symmetry that is restored by making each copy of the repository a branch.
PXSL ("pixel") is a convenient shorthand for writing markup-heavy XML documents. It provides XML authors and programmers with a simple, concise syntax that they can use to create XML documents. For more advanced users, it offers customizable shortcuts and sophisticated refactoring tools like functional macros that can markedly reduce the size and complexity of markup-dense XML documents.
CMI is an optimizing frontend for gcc which allows gcc to inline across module boundaries without requiring you to put inline functions in header files or even mark inline functions for inlining. It makes your code go faster, makes your code smaller, makes your embedded software use less stack space, is a preprocessor for gcc, supports most gcc extensions, and is able to deal with such notoriously tricky code as the glibc header files. It works by merging multiple C files into one file, topologically sorting the definitions so that definitions come before uses, and marks functions as inline. It controls code bloat by deleting dead code and inlining up until a user-specified budget is reached. You can use user-specified heuristics to select which functions to inline (it includes a tool which uses gprof output to choose inlinings to illustrate this).
Parsec is a monadic parser combinator library for Haskell. It can parse context-sensitive, infinite look-ahead grammars but performs best on predictive (LL) grammars. The parser definition is in the same language as the rest of the program, so it benefits from type checking and existing development tools. Parsers are first-class values within the language and it is easy to extend the set of parsers with custom-made ones.
Happy is a parser generator system for Haskell, similar to the tool 'yacc' for C. Like yacc, it takes a file containing an annotated BNF specification of a grammar and produces a Haskell module containing a parser for the grammar. It is flexible: you can have several Happy parsers in the same program, and several entry points to a single grammar. It can work in conjunction with a lexical analyser supplied by the user (either hand-written or generated by another program), or it can parse a stream of characters directly (but this isn't practical in most cases).