<s>
urbiscript	B-Language
is	O
a	O
programming	O
language	O
for	O
robotics	O
.	O
</s>
<s>
It	O
features	O
syntactic	O
support	O
for	O
concurrency	O
and	O
event-based	B-Application
programming	I-Application
.	O
</s>
<s>
It	O
is	O
a	O
prototype-based	B-Application
object-oriented	B-Language
scripting	B-Language
language	I-Language
.	O
</s>
<s>
It	O
is	O
dynamic	O
:	O
name	B-Application
resolution	I-Application
is	O
performed	O
during	O
the	O
program	O
execution	O
(	O
late	O
binding	O
)	O
;	O
slots	O
(	O
member	B-Application
variables	I-Application
)	O
can	O
be	O
added/removed	O
at	O
runtime	O
,	O
and	O
even	O
prototypes	O
(	O
superclasses	O
)	O
of	O
an	O
object	O
can	O
be	O
changed	O
at	O
runtime	O
.	O
</s>
<s>
Memory	B-General_Concept
management	I-General_Concept
is	O
performed	O
by	O
reference	B-General_Concept
counting	I-General_Concept
.	O
</s>
<s>
Tightly	O
bound	O
to	O
the	O
Urbi	B-Application
platform	I-Application
it	O
supports	O
seamless	O
integration	O
of	O
C++	B-Language
/Java	O
components	O
.	O
</s>
<s>
From	O
the	O
syntactical	O
point	O
of	O
view	O
,	O
urbiscript	B-Language
belongs	O
to	O
the	O
C-family	O
of	O
programming	O
languages	O
.	O
</s>
<s>
Its	O
prototype-based	B-Application
object-oriented	B-Language
design	O
was	O
influenced	O
by	O
the	O
Self	B-Operating_System
and	O
the	O
Io	B-Application
programming	I-Application
languages	I-Application
.	O
</s>
<s>
It	O
is	O
designed	O
to	O
program	O
,	O
but	O
also	O
interact	O
with	O
robots	O
;	O
as	O
such	O
,	O
it	O
is	O
influenced	O
by	O
Unix	B-Application
shells	I-Application
and	O
other	O
languages	O
that	O
provide	O
a	O
read-eval-print	B-Application
loop	I-Application
style	O
interactive	O
toplevel	O
.	O
</s>
<s>
urbiscript	B-Language
statements	O
include	O
(	O
among	O
others	O
)	O
:	O
</s>
<s>
The	O
traditional	O
for	B-Language
statement	I-Language
,	O
as	O
in	O
C	B-Language
which	O
iterates	O
over	O
an	O
iterable	O
object	O
,	O
capturing	O
each	O
element	O
to	O
a	O
local	O
variable	O
for	O
use	O
by	O
the	O
attached	O
block	O
.	O
</s>
<s>
Another	O
for	B-Language
statement	I-Language
,	O
which	O
iterates	O
over	O
an	O
iterable	O
object	O
,	O
capturing	O
each	O
element	O
to	O
a	O
local	O
variable	O
for	O
use	O
by	O
the	O
attached	O
block	O
.	O
</s>
<s>
urbiscript	B-Language
also	O
feature	O
assert	O
blocks	O
,	O
which	O
can	O
be	O
used	O
to	O
factor	O
several	O
assert	O
statements	O
.	O
</s>
<s>
Actually	O
,	O
contrary	O
to	O
most	O
C-like	O
languages	O
and	O
despite	O
what	O
the	O
syntax	O
suggests	O
,	O
statements	O
"	O
have	O
a	O
value	O
"	O
,	O
and	O
therefore	O
are	O
expressions	O
,	O
provided	O
they	O
are	O
embedded	O
in	O
braces	O
:	O
</s>
<s>
In	O
urbiscript	B-Language
,	O
some	O
control-flow	O
constructs	O
come	O
in	O
several	O
"	O
flavors	O
"	O
:	O
two	O
types	O
of	O
sequential	O
composition	O
,	O
and	O
two	O
types	O
of	O
concurrent	O
composition	O
.	O
</s>
<s>
Under	O
the	O
hood	O
,	O
concurrency	O
is	O
implemented	O
using	O
coroutines	B-Architecture
.	O
</s>
<s>
Like	O
in	O
C	B-Language
,	O
the	O
semicolon	O
denotes	O
sequential	O
composition	O
:	O
a	O
;	O
b	O
stands	O
for	O
"	O
run	O
statement	O
a	O
then	O
run	O
statement	O
b	O
.	O
</s>
<s>
Similarly	O
urbiscript	B-Language
features	O
two	O
means	O
to	O
compose	O
statements	O
concurrently	O
.	O
</s>
<s>
This	O
is	O
very	O
similar	O
to	O
the	O
&	B-Operating_System
operator	O
in	O
Unix	B-Application
shells	I-Application
.	O
</s>
<s>
Most	O
looping	O
constructs	O
in	O
urbiscript	B-Language
come	O
in	O
several	O
"	O
flavors	O
"	O
,	O
which	O
are	O
based	O
on	O
the	O
four	O
statement	O
separators	O
:	O
;	O
,	O
|	O
,	O
,,	O
and	O
&	B-Operating_System
.	O
</s>
<s>
Aiming	O
at	O
the	O
development	O
of	O
portable	O
robotic	O
applications	O
,	O
urbiscript	B-Language
relies	O
on	O
specific	O
syntactic	O
constructs	O
to	O
specify	O
reactive	O
behaviors	O
such	O
as	O
"	O
go	O
to	O
the	O
charging	O
dock	O
when	O
the	O
battery	O
is	O
low	O
"	O
,	O
"	O
play	O
a	O
friendly	O
sound	O
when	O
a	O
known	O
face	O
is	O
recognized	O
"	O
,	O
or	O
"	O
stop	O
when	O
an	O
obstacle	O
is	O
detected	O
"	O
.	O
</s>
<s>
The	O
urbiscript	B-Language
language	O
also	O
allows	O
to	O
monitor	O
expressions	O
:	O
</s>
