<s>
wxHaskell	B-Language
is	O
a	O
portable	O
and	O
native	O
GUI	B-Application
library	O
for	O
Haskell	B-Language
,	O
built	O
on	O
wxWidgets	B-Language
.	O
</s>
<s>
It	O
is	O
often	O
used	O
by	O
those	O
wanting	O
to	O
develop	O
a	O
GUI	B-Application
with	O
a	O
functional	B-Language
language	I-Language
.	O
</s>
<s>
wxHaskell	B-Language
is	O
a	O
middle-level	O
GUI	B-Application
library	O
.	O
</s>
<s>
Several	O
experimental	O
high-level	O
GUI	B-Application
library	O
approaches	O
are	O
implemented	O
on	O
top	O
of	O
wxHaskell	B-Language
:	O
</s>
<s>
In	O
contrast	O
,	O
the	O
high-level	O
GUI	B-Application
libraries	O
and	O
are	O
implemented	O
on	O
top	O
of	O
the	O
middle-level	O
Gtk2Hs	O
,	O
which	O
is	O
based	O
on	O
GTK2	B-Application
.	O
</s>
<s>
All	O
of	O
these	O
high-level	O
libraries	O
are	O
experimental	O
,	O
using	O
advanced	O
mathematical	O
concepts	O
in	O
their	O
approach	O
(	O
see	O
arrows	B-Application
in	I-Application
functional	I-Application
programming	I-Application
)	O
.	O
</s>
