Haskell IDoc extracts interface documentation and declarations from Haskell modules based on standard Haskell layout rules and a small number of clues that the programmer embeds in interface comments. These clues have been designed to be visually non-imposing when displaying the source in a text editor. Interface documentation is rendered in standard markup languages. IDoc has been designed to be simple to use and install.
DrIFT is a type sensitive preprocessor for Haskell. It extracts type declarations and directives from modules and applies rules to them which generate code. It is intended that the user can add new rules as required. DrIFT automates instance derivation for classes that aren't supported by the standard compilers. In addition, instances can be produced in separate modules to that containing the type declaration. This allows instances to be derived for a type after the original module has been compiled. Simple utility functions can also be produced from a type.
hmake is a compilation manager for Haskell programs. It is compiler independent, and liberates the programmer from needing to write Makefiles by extracting dependencies directly from the source code. It is aware of all compiler invocation conventions, and of several common pre-processors, including cpp, greencard, hsc2hs, c2hs, and happy.
HaXml is a suite of libraries and tools for manipulating XML documents in Haskell. It includes a parser, a pretty-printer, a validator, a combinator library for transforming documents, and converters for changing a Haskell datatype into an XML DTD, and for changing an XML DTD into a set of Haskell datatypes. There are also tools for a query language based on XQL.
Hat (Haskell Tracer) is a tracing and debugging system for Haskell that can be used for comprehending working programs, and debugging an incorrect one. It consists of hat-trans, which transforms a program into one that traces itself using your normal compiler and a runtime library, and a set of browsing tools that explore the trace after execution of the program has completed.