The hat package

[Tags:library, program]

hat-trans transforms Module.hs into Hat/Module.hs such that when the program is executed, a trace file Programname.hat is generated. Various tools (hat-trail, hat-observe, hat-explore ...) then allow viewing the trace file in different ways, to locate a bug or understand how a program works. This is the first release of Hat under Cabal. It is the least possible update to make Hat work with Cabal. Hat 2.07 works only with ghc for Haskell 98 (plus a few extensions) and the standard Haskell 98 libraries plus some Haskell 2010 libraries. Although it should build on any operating system, most viewing tools use ASCII console escape sequences and they open xterms; hence they will only work well under Unix and X11. Installation: > cabal -v install Flag -v allows you to see what is going on. Building takes a long time (one module has 25.000 lines of code). Don't worry about numerous warning messages. Use: > hat-make MyProgram.hs transforms and compiles all modules of your program and produces the tracing version Hat/MyProgram. Run your program > Hat/MyProgram which will produce trace files MyProgram.hat* Use the viewing tools to explore the trace: > hat-trail / hat-observe / hat-explore /... MyProgram There is documentation in the "docs" folder, but much of it is outdated. There are a few small programs for exploring tracing in the "examples" folder.


Dependencies base (==4.*), bytestring (==0.9.*), containers (==0.4.*), directory (==1.1.*), haskeline (==0.6.*), old-locale (==1.0.*), old-time (==1.1.*), process (==1.1.*), random (==1.0.*) [details]
License OtherLicense
Copyright (c) 2000-2012 Hat team
Author Hat team
Stability provisional
Category Development
Home page
Bug tracker
Source repository head: git clone git://
Uploaded Fri Nov 2 17:20:31 UTC 2012 by OlafChitil
Distributions NixOS:
Downloads 3180 total (47 in the last 30 days)
0 []
Status Docs not available [build log]
All reported builds failed as of 2015-11-20 [all 4 reports]


  • Hat
    • Hat.Array
    • Hat.CPUTime
    • Hat.Char
    • Hat.Complex
    • Control
      • Hat.Control.Monad
    • Data
      • Hat.Data.Char
      • Hat.Data.List
      • Hat.Data.Maybe
    • Hat.Directory
    • Hat.Hack
    • Hat.Hat
    • Hat.IO
    • Hat.Ix
    • Hat.List
    • Hat.Locale
    • Hat.Maybe
    • Hat.Monad
    • Hat.Numeric
    • Hat.Prelude
    • Hat.PreludeBasic
    • Hat.Random
    • Hat.Ratio
    • Hat.System
      • Hat.System.Environment
      • Hat.System.Exit
      • Hat.System.IO
    • Hat.Time


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