<s>
Lustre	B-Application
is	O
a	O
formally	B-Architecture
defined	I-Architecture
,	O
declarative	B-Language
,	O
and	O
synchronous	B-Language
dataflow	B-Application
programming	I-Application
language	I-Application
for	O
programming	O
reactive	O
systems	O
.	O
</s>
<s>
In	O
1993	O
it	O
progressed	O
to	O
practical	O
,	O
industrial	O
use	O
in	O
a	O
commercial	O
product	O
as	O
the	O
core	O
language	O
of	O
the	O
industrial	O
environment	O
SCADE	O
,	O
developed	O
by	O
Esterel	B-Language
Technologies	O
.	O
</s>
<s>
A	O
Lustre	B-Application
program	O
is	O
a	O
series	O
of	O
node	O
definitions	O
,	O
written	O
as	O
:	O
</s>
