<s>
Tamarin	B-Language
is	O
a	O
discontinued	O
free	B-Application
software	I-Application
virtual	B-Architecture
machine	I-Architecture
with	O
just-in-time	O
compilation	O
(	O
JIT	O
)	O
support	O
intended	O
to	O
implement	O
the	O
4th	O
edition	O
of	O
the	O
ECMAScript	B-Language
(	O
ES4	O
)	O
language	O
standard	O
.	O
</s>
<s>
Tamarin	B-Language
source	O
code	O
originates	O
from	O
ActionScript	B-Language
Virtual	I-Language
Machine	I-Language
2	I-Language
(	O
AVM2	B-Language
)	O
developed	O
by	O
Adobe	O
Systems	O
,	O
as	O
introduced	O
within	O
Adobe	B-Operating_System
Flash	I-Operating_System
Player	I-Operating_System
9	O
,	O
which	O
implements	O
ActionScript	B-Operating_System
3	O
scripting	O
language	O
.	O
</s>
<s>
ActionScript	B-Language
Virtual	I-Language
Machine	I-Language
2	I-Language
was	O
donated	O
as	O
open-source	B-Application
to	O
Mozilla	B-Operating_System
Foundation	I-Operating_System
on	O
November	O
7	O
,	O
2006	O
,	O
to	O
develop	O
Tamarin	B-Language
as	O
a	O
high-performance	O
virtual	B-Architecture
machine	I-Architecture
,	O
with	O
the	O
support	O
from	O
broad	O
Mozilla	B-Operating_System
community	O
,	O
to	O
be	O
used	O
by	O
Mozilla	B-Operating_System
and	O
Adobe	O
Systems	O
in	O
the	O
next	O
generation	O
of	O
their	O
JavaScript	B-Language
and	O
ActionScript	B-Operating_System
engines	B-Language
with	O
the	O
ultimate	O
aim	O
to	O
unify	O
the	O
scripting	O
languages	O
across	O
web	B-Application
browsers	I-Application
and	O
Adobe	B-Operating_System
Flash	I-Operating_System
platform	I-Operating_System
and	O
ease	O
the	O
development	O
of	O
better	O
performing	O
rich	O
web	B-Application
applications	I-Application
.	O
</s>
<s>
The	O
source	O
code	O
,	O
including	O
the	O
just-in-time	O
compiler	O
and	O
conservative	O
garbage	B-General_Concept
collector	I-General_Concept
,	O
was	O
donated	O
to	O
the	B-Operating_System
Mozilla	I-Operating_System
Foundation	I-Operating_System
on	O
November	O
7	O
,	O
2006	O
.	O
</s>
<s>
The	O
contributed	O
code	O
is	O
tri-licensed	O
under	O
the	O
GPL	B-License
,	O
LGPL	B-Application
,	O
and	O
MPL	B-License
licenses	I-License
to	O
be	O
developed	O
in	O
Mozilla	B-Operating_System
's	O
Mercurial	B-Protocol
repository	O
.	O
</s>
<s>
The	O
contributed	O
code	O
is	O
approximately	O
135,000	O
lines	O
of	O
code	O
,	O
making	O
it	O
the	O
largest	O
single	O
donation	O
of	O
code	O
to	O
the	O
Mozilla	B-Operating_System
project	I-Operating_System
besides	O
Netscape	B-Protocol
itself	O
.	O
</s>
<s>
There	O
were	O
plans	O
to	O
use	O
Tamarin	B-Language
as	O
part	O
of	O
Mozilla	B-Operating_System
2	O
(	O
and	O
therefore	O
Firefox	B-Application
4	O
)	O
.	O
</s>
<s>
The	O
project	O
to	O
integrate	O
Tamarin	B-Language
and	O
SpiderMonkey	B-Language
was	O
called	O
"	O
ActionMonkey	O
"	O
,	O
but	O
was	O
canceled	O
in	O
2008	O
because	O
Tamarin	B-Language
's	O
interpreter	O
turned	O
out	O
to	O
be	O
slower	O
than	O
SpiderMonkey	B-Language
's	O
and	O
because	O
the	O
plans	O
of	O
ECMAScript	B-Language
development	O
shifted	O
from	O
ECMAScript	B-Language
4	O
,	O
which	O
was	O
partially	O
implemented	O
by	O
then	O
existing	O
Tamarin	B-Language
source	O
code	O
and	O
was	O
meant	O
to	O
be	O
completed	O
by	O
joined	O
efforts	O
of	O
Adobe	O
,	O
Mozilla	B-Operating_System
and	O
its	O
community	O
within	O
the	O
Tamarin	B-Language
Project	I-Language
,	O
to	O
ECMAScript	B-Language
Harmony	O
.	O
</s>
<s>
Adobe	O
continued	O
to	O
use	O
Tamarin	B-Language
in	O
its	O
Flash	B-Operating_System
Player	I-Operating_System
,	O
but	O
it	O
did	O
not	O
replace	O
SpiderMonkey	B-Language
as	O
the	O
JavaScript	B-Language
engine	I-Language
of	O
Mozilla	B-Operating_System
applications	O
.	O
</s>
<s>
The	O
only	O
part	O
of	O
Tamarin	B-Language
used	O
in	O
modern	O
Mozilla	B-Operating_System
applications	O
(	O
i.e.	O
</s>
<s>
Firefox	B-Application
3.5	O
+	O
)	O
via	O
SpiderMonkey	B-Language
is	O
NanoJIT	O
,	O
a	O
module	O
that	O
is	O
used	O
to	O
generate	O
native	O
code	O
when	O
performing	O
just-in-time	O
compilation	O
.	O
</s>
<s>
Adobe	O
contributed	O
code	O
for	O
its	O
ActionScript	B-Language
Virtual	I-Language
Machine	I-Language
2	I-Language
and	O
the	O
JIT	O
compiler	O
.	O
</s>
<s>
The	O
ActionScript	B-Operating_System
compiler	O
is	O
also	O
open	O
source	O
as	O
a	O
part	O
of	O
Adobe	B-Operating_System
Flex	I-Operating_System
.	O
</s>
<s>
There	O
is	O
also	O
CrossBridge	B-Language
,	O
an	O
open	O
source	O
C	B-Language
and	O
C++	B-Language
compiler	O
.	O
</s>
<s>
Tamarin	B-Language
is	O
not	O
the	O
same	O
as	O
Adobe	B-Operating_System
Flash	I-Operating_System
Player	I-Operating_System
,	O
which	O
remains	O
closed	O
source	O
.	O
</s>
<s>
The	O
Tamarin	B-Language
virtual	B-Architecture
machine	I-Architecture
is	O
only	O
a	O
part	O
of	O
Flash	B-Operating_System
Player	I-Operating_System
.	O
</s>
<s>
Two	O
projects	O
related	O
to	O
Tamarin	B-Language
were	O
announced	O
on	O
July	O
25	O
,	O
2007	O
,	O
in	O
Brendan	O
Eich	O
's	O
keynote	O
at	O
The	O
Ajax	O
Experience	O
West	O
:	O
IronMonkey	O
and	O
ScreamingMonkey	B-Language
.	O
</s>
<s>
IronMonkey	O
is	O
a	O
project	O
to	O
map	O
IronPython	B-Application
and	O
IronRuby	B-Language
to	O
Tamarin	B-Language
led	O
by	O
Seo	O
Sanghyeon	O
.	O
</s>
<s>
ScreamingMonkey	B-Language
's	O
goal	O
is	O
to	O
allow	O
Tamarin	B-Language
to	O
run	O
within	O
non-Mozilla	O
browsers	B-Application
(	O
thus	O
allowing	O
them	O
to	O
understand	O
JavaScript	B-Language
2	O
)	O
,	O
starting	O
with	O
Internet	B-Application
Explorer	I-Application
.	O
</s>
<s>
Both	O
SpiderMonkey	B-Language
and	O
Tamarin	B-Language
fulfill	O
closely	O
related	O
goals	O
and	O
so	O
were	O
given	O
names	O
derived	O
from	O
types	O
of	O
monkeys	O
(	O
the	O
spider	O
monkey	O
and	O
the	O
tamarin	B-Language
,	O
respectively	O
)	O
.	O
</s>
