<s>
Zonnon	B-Language
is	O
a	O
general	O
purpose	O
programming	O
language	O
in	O
the	O
line	O
or	O
family	O
of	O
the	O
preceding	O
languages	O
Pascal	B-Application
,	O
Modula	B-Language
,	O
and	O
Oberon	B-Language
.	O
</s>
<s>
Its	O
conceptual	O
model	O
is	O
based	O
on	O
objects	O
,	O
definitions	O
,	O
implementations	O
,	O
and	O
modules	B-Architecture
.	O
</s>
<s>
Zonnon	B-Language
introduces	O
the	O
concept	O
of	O
'	O
active	O
objects	O
 '	O
which	O
are	O
used	O
to	O
represent	O
real	O
world	O
concurrent	O
objects	O
within	O
computer	O
programs	O
.	O
</s>
<s>
The	O
Zonnon	B-Language
Language	O
Report	O
was	O
written	O
by	O
Brian	O
Kirk	O
(	O
director	O
at	O
Robinsons	O
Associates	O
)	O
,	O
and	O
David	O
Lightfoot	O
(	O
Oxford	O
Brookes	O
University	O
)	O
working	O
with	O
Gutknecht	O
(	O
ETH	O
,	O
Zürich	O
)	O
and	O
Dr.	O
Eugene	O
Zueff	O
( Евгений	O
Зуев	O
)	O
(	O
Moscow	O
State	O
University	O
)	O
.	O
</s>
<s>
The	O
first	O
book	O
about	O
Zonnon	B-Language
was	O
published	O
by	O
the	O
N	O
.	O
I	O
.	O
Lobachevsky	O
State	O
University	O
of	O
Nizhny	O
Novgorod	O
(	O
a.k.a.	O
,	O
Nizhni	O
Novgorod	O
State	O
University	O
)	O
.	O
</s>
<s>
Zonnon	B-Language
is	O
a	O
member	O
of	O
the	O
Pascal	B-Application
family	O
of	O
languages	O
,	O
which	O
has	O
two	O
beneficial	O
consequences	O
:	O
a	O
)	O
it	O
is	O
a	O
general	O
purpose	O
language	O
and	O
b	O
)	O
it	O
is	O
immediately	O
familiar	O
to	O
programmers	O
who	O
have	O
used	O
Pascal	B-Application
,	O
Modula-2	O
,	O
and	O
Oberon	B-Language
.	O
</s>
<s>
Most	O
Pascal	B-Application
programs	O
from	O
the	O
domain	O
of	O
algorithms	O
and	O
data	O
structures	O
are	O
successfully	O
compiled	B-Language
by	O
the	O
Zonnon	B-Language
compiler	B-Language
after	O
a	O
few	O
minor	O
modifications	O
.	O
</s>
<s>
However	O
,	O
from	O
the	O
perspective	O
of	O
programming	B-Application
in	I-Application
the	I-Application
large	I-Application
,	O
Zonnon	B-Language
is	O
much	O
more	O
elaborate	O
compared	O
to	O
its	O
predecessors	O
.	O
</s>
<s>
Zonnon	B-Language
has	O
four	O
different	O
kinds	O
of	O
program	O
units	O
:	O
objects	O
,	O
modules	B-Architecture
,	O
definitions	O
,	O
and	O
implementations	O
.	O
</s>
<s>
The	O
first	O
two	O
are	O
instantiated	O
at	B-Library
runtime	I-Library
,	O
the	O
third	O
is	O
a	O
compile	B-Application
time	I-Application
unit	O
of	O
abstraction	O
,	O
and	O
the	O
fourth	O
is	O
a	O
unit	O
of	O
composition	O
.	O
</s>
<s>
Module	B-Architecture
can	O
be	O
considered	O
as	O
a	O
singleton	O
object	O
which	O
creation	O
is	O
controlled	O
by	O
the	O
system	O
.	O
</s>
<s>
In	O
addition	O
,	O
a	O
module	B-Architecture
may	O
act	O
as	O
a	O
container	O
of	O
logically	O
connected	O
abstract	O
data	O
types	O
,	O
operators	O
,	O
and	O
structural	O
units	O
of	O
the	O
runtime	B-Library
environment	O
.	O
</s>
<s>
In	O
combination	O
with	O
the	O
import	O
relation	O
,	O
the	O
module	B-Architecture
construct	O
is	O
a	O
powerful	O
system	O
structuring	O
tool	O
.	O
</s>
<s>
Definition	O
is	O
an	O
abstract	O
view	O
on	O
an	O
object	O
(	O
or	O
on	O
a	O
module	B-Architecture
)	O
from	O
a	O
certain	O
perspective	O
.	O
</s>
<s>
It	O
is	O
a	O
unit	O
of	O
reuse	O
and	O
composition	O
that	O
is	O
aggregated	O
into	O
the	O
state	O
space	O
of	O
an	O
object	O
(	O
or	O
module	B-Architecture
)	O
,	O
either	O
at	O
compile	B-Application
time	I-Application
or	O
at	B-Library
runtime	I-Library
.	O
</s>
<s>
Zonnon	B-Language
uses	O
a	O
compositional	O
inheritance	O
model	O
based	O
on	O
aggregation	O
.	O
</s>
<s>
Typically	O
,	O
an	O
object	O
(	O
or	O
module	B-Architecture
)	O
is	O
composed	O
of	O
several	O
functional	O
components	O
,	O
each	O
of	O
them	O
presenting	O
itself	O
to	O
clients	O
in	O
the	O
form	O
of	O
an	O
abstract	O
definition	O
.	O
</s>
<s>
Zonnon	B-Language
allows	O
adding	O
behavior	O
to	O
objects	O
(	O
and	O
modules	B-Architecture
)	O
.	O
</s>
<s>
For	O
this	O
purpose	O
,	O
the	O
notion	O
of	O
active	O
object	O
was	O
imported	O
from	O
the	O
Active	O
Oberon	B-Language
language	O
and	O
generalized	O
towards	O
a	O
unified	O
model	O
of	O
hierarchic	O
activities	O
.	O
</s>
