This program just opens a small window displaying the message "Hello, world!". The window will look something like this (depending on your setup):
Here is the source code:
import Fudgets main = fudlogue (shellF "Hello" (labelF "Hello, world!"))
Fudgets
. Assuming the Fudgets library has been
installed (with cabal install
) and the program is
stored in a file called Hello.hs
, the command line
to compile the program is
ghc Hello
A fudget program consists of a number of fudgets combined in a
hierarchical structure into one main fudget. The function
fudlogue
is used to connect the main fudget to the Haskell I/O system.
It also handles various initialisation and administration.
A fudget program with a graphical user interface needs one or more
shell windows (top level windows). These can be created with
the function
shellF
.
The last argument is the fudget which determines the contents of the
window.
In this simple program, the contents of the shell window is just a
simple string display, which is created with the function
labelF
.
The argument is the string to be displayed.