<s>
Sather	B-Application
is	O
an	O
object-oriented	B-Language
programming	I-Language
language	I-Language
.	O
</s>
<s>
It	O
supports	O
garbage	B-General_Concept
collection	I-General_Concept
and	O
generics	B-Language
by	O
subtypes	O
.	O
</s>
<s>
Originally	O
,	O
it	O
was	O
based	O
on	O
Eiffel	B-Language
,	O
but	O
it	O
has	O
diverged	O
,	O
and	O
now	O
includes	O
several	O
functional	B-Language
programming	I-Language
features	O
.	O
</s>
<s>
The	O
name	O
is	O
inspired	O
by	O
Eiffel	B-Language
;	O
the	O
Sather	B-Application
Tower	O
is	O
a	O
recognizable	O
landmark	O
at	O
Berkeley	O
,	O
named	O
after	O
Jane	O
Krom	O
Sather	B-Application
,	O
the	O
widow	O
of	O
Peder	O
Sather	B-Application
,	O
who	O
donated	O
large	O
sums	O
to	O
the	O
foundation	O
of	O
the	O
university	O
.	O
</s>
<s>
Sather	B-Application
also	O
takes	O
inspiration	O
from	O
other	O
programming	O
languages	O
and	O
paradigms	O
:	O
iterators	O
,	O
design	B-Application
by	I-Application
contract	I-Application
,	O
abstract	O
classes	O
,	O
multiple	B-Application
inheritance	I-Application
,	O
anonymous	B-General_Concept
functions	I-General_Concept
,	O
operator	O
overloading	O
,	O
contravariant	O
type	O
system	O
.	O
</s>
<s>
The	O
original	O
Berkeley	O
implementation	O
(	O
last	O
stable	O
version	O
1.1	O
was	O
released	O
in	O
1995	O
,	O
no	O
longer	O
maintained	O
)	O
has	O
been	O
adopted	O
by	O
the	B-Operating_System
Free	I-Operating_System
Software	I-Operating_System
Foundation	I-Operating_System
therefore	O
becoming	O
GNU	O
Sather	B-Application
.	O
</s>
<s>
There	O
were	O
several	O
other	O
variants	O
:	O
Sather-K	O
from	O
the	O
University	O
of	O
Karlsruhe	O
;	O
Sather-W	O
from	O
the	O
University	O
of	O
Waikato	O
(	O
implementation	O
of	O
Sather	B-Application
version	O
1.3	O
)	O
;	O
Peter	O
Naulls	O
 '	O
port	O
of	O
ICSI	O
Sather	B-Application
1.1	O
to	O
RISC	B-Operating_System
OS	I-Operating_System
;	O
and	O
pSather	O
,	O
a	O
parallel	O
version	O
of	O
ICSI	O
Sather	B-Application
addressing	O
non-uniform	B-Operating_System
memory	I-Operating_System
access	I-Operating_System
multiprocessor	O
architectures	O
but	O
presenting	O
a	O
shared	O
memory	O
model	O
to	O
the	O
programmer	O
.	O
</s>
<s>
The	O
former	O
ICSI	O
Sather	B-Application
compiler	O
(	O
now	O
GNU	O
Sather	B-Application
)	O
is	O
implemented	O
as	O
a	O
compiler	O
to	O
C	B-Language
,	O
i.e.	O
,	O
the	O
compiler	O
does	O
not	O
output	O
object	B-Application
or	O
machine	B-Language
code	I-Language
,	O
but	O
takes	O
Sather	B-Application
source	O
code	O
and	O
generates	O
C	B-Language
source	O
code	O
as	O
an	O
intermediate	O
language	O
.	O
</s>
<s>
Optimizing	O
is	O
left	O
to	O
the	O
C	B-Language
compiler	O
.	O
</s>
<s>
The	O
GNU	O
Sather	B-Application
compiler	O
,	O
written	O
in	O
Sather	B-Application
itself	O
,	O
is	O
dual	B-License
licensed	I-License
under	O
the	O
GNU	B-License
GPL	I-License
&	O
LGPL	B-Application
.	O
</s>
