# Hat download page

The latest stable release of Hat is 2.04, available in various distribution formats (listed below). Important patches for the stable version are also provided. The development tree is at version 2.05 and is only available by CVS. Bugfixes and important changes to the system are described in the release notes for each version.

Don't forget to read the system requirements, first, and then the installation instructions.

### Distribution packages

package | machine | version | date | size
--- | --- | --- | --- | ---
Sources (.tar.gz) | any | 2.04 | 2005-05-17 | 1.6Mb
Sources (.tar.gz) | any | 2.02 | 2003-03-26 | 1.4Mb
Sources (.tar.gz) | any | 2.00 | 2002-06-14 | 1.5Mb

Alternative locations:
Tarfiles and RPMs:
`ftp://ftp.cs.york.ac.uk/pub/haskell/hat/`
`http://www.cs.york.ac.uk/fp/hat/hat-2.04.tar.gz`
RPMs for RedHat:
`http://www.dtek.chalmers.se/~d95mback/nhc98/`
`http://haskell.org/~petersen/rpms/i386/`
`http://haskell.org/~petersen/srpms/`
FreeBSD port:
`http://freshports.org/devel/hs-hat/`
Darwin port:
`http://darwinports.opendarwin.org//`
Debian packages:
`ftp://ftp.debian.org/debian/pool/main/h/hat/`

Known to work with the following compiler versions upwards:

nhc98 | 1.18
ghc | 5.04.2
ghc | 6.0.1

All the documents available on the web are included in the source package. (* Please note that options/instructions for out-of-date packages may differ slightly from the ones on the web. Always follow the instructions from the package itself.)

The installation instructions should be comprehensive, but if you have any problems, please mail `hat@haskell.org`. (You do not need to be a member of the list to post to it.)

### Patches

patch name | patch to | date | fixes what problem?
--- | --- | --- | ---
- | hat v2.04 | 2005-05-17 | There are no patches for 2.04 yet.
cumulative | hat v2.02 | 2003-04-30 | This patch is a cumulative patch that includes the two listed below (redefine and typesyn), and in addition fixes the following problem: In the transformation of a module that defines instances of an imported class whose methods are only in scope qualified, any generated uses of the method names must be qualified too.
redefine | hat v2.02 | 2003-04-24 | A Prelude entity redefined in a user module led to some overlapping auxiliary functions in the hat-transformed module. This patch ensures that a Prelude function is not imported if there is a local redefinition.
typesyn | hat v2.02 | 2003-04-24 | Some complex type synonyms (renaming arrow (function) types) led to incorrect types in the hat-transformed code.
hmake3.06 | hat v2.00 | 2002-10-14 | Enable hat-trans to build with the latest version of hmake (3.06).
pretty-printer | hat v2.00 | 2002-08-28 | Fix a pretty-printing bug in hat-trans, e.g. the transformed version of `f = \ ~(a,b) -> 1` was printed wrongly.
ntohl | hat v2.00 | 2002-07-12 | On some machines (e.g. Solaris), an extra #include is needed to get hold of the ntohl() macro.
script/echo.c | hat v2.00 | 2002-06-19 | This file is missing from the distribution tarfile. You will only need it on platforms where the builtin `echo' command does not understand the `-n' option.

The latest updates to these pages are available on the WWW from `http://www.haskell.org/hat/`
`http://www.cs.york.ac.uk/fp/hat/`

This page last modified: 17th May 2005
York Functional Programming Group