fudgets: The Fudgets Library

[ concurrency, gui, library, network, program ] [ Propose Tags ]

Fudgets is a Graphical User Interface Toolkit built in Haskell on top of the X11 Windows system in the early 1990s. There is an FPCA-93 paper about it. Fudgets also makes it easy to create client/server applications that communicate via the Internet.

This package includes the Fudgets library and a few small examples and demo applications.

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Versions [RSS] 0.18.3,
Change log ChangeLog.md
Dependencies array, base (>=4 && <5), containers, directory (>=1.2.3), fudgets, old-time, parallel, process, random, time, unix [details]
License LicenseRef-OtherLicense
Author Thomas Hallgren and Magnus Carlsson and others
Maintainer Thomas Hallgren
Category GUI, Network, Concurrency
Home page https://www.altocumulus.org/Fudgets/
Uploaded by ThomasHallgren at 2022-03-15T12:09:58Z
Distributions NixOS:
Executables doRequest, XMine, Tiles, Life, FudPaint, Explore, SpaceInvaders2, FancyHello, texteditor, StopWatch, fudgetclock, Graph
Downloads 58 total (4 in the last 30 days)
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Status Docs available [build log]
Last success reported on 2022-03-15 [all 1 reports]

Readme for fudgets-

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¤ Fudgets ¤

Fudgets is primarily a Graphical User Interface Toolkit implemented in Haskell on top of its own binding to the Xlib library of the X Windows system. Fudgets also makes it easy to create client/server applications that communicate via the Internet. The Hello world program fits on a single line:

main = fudlogue (shellF "Hello" (labelF "Hello world!"))

The key abstraction is the fudget. A fudget is a stream processor with high-level and low-level streams. The high level streams are used for communication between fudgets within a program. The low level streams are for communication with the I/O system.

Fudgets are combined using various combinators for parallel composition, serial composition and loops.

Fudgets was originally implemented in Lazy ML in the early 1990s, then converted to Haskell. It was thus designed before monadic IO was introduced in Haskell and early versions did not make use of Haskell's type classes at all.


Installing Fudgets from Hackage

On Linux systems

  • sudo apt install libxext-dev (installs Xlib etc on Debian-based distributions, the command will be different on other Linux distributions.)
  • cabal install fudgets

On macOS

  • Install XQuartz.

  • brew install gcc (need the version of cpp included with gcc, since there are some issues with cpp from clang. Note: fudgets.cabal refers to cpp-11, you might need to change this if you install a different version of gcc.)

  • If you are using ghc>=8.10.3: unfortunately it seems that the -pgmP option no longer works, so you need to change a line in $PREFIX/lib/ghc-*/lib/settings instead:

      ,("Haskell CPP command", "gcc-11")

  • cabal install fudgets