<s>
incr	B-Application
Tcl	I-Application
(	O
commonly	O
stylised	O
as	O
[	O
incr	O
Tcl ]	O
,	O
and	O
often	O
abbreviated	O
to	O
itcl	B-Application
)	O
is	O
a	O
set	O
of	O
object-oriented	B-Language
extensions	O
for	O
the	O
Tcl	B-Operating_System
programming	I-Operating_System
language	I-Operating_System
.	O
</s>
<s>
It	O
is	O
widely	O
used	O
among	O
the	O
Tcl	B-Operating_System
community	O
,	O
and	O
is	O
generally	O
regarded	O
as	O
industrial	O
strength	O
.	O
</s>
<s>
Its	O
name	O
is	O
a	O
pun	O
on	O
"	O
C++	B-Language
"	O
.	O
</s>
<s>
Itcl	B-Application
implementations	O
exist	O
as	O
both	O
a	O
package	O
that	O
may	O
be	O
dynamically	O
loaded	O
by	O
a	O
Tcl	B-Operating_System
application	O
,	O
as	O
well	O
as	O
an	O
independent	O
standalone	O
language	O
with	O
its	O
own	O
interpreter	O
.	O
</s>
<s>
Itcl	B-Application
allows	O
namespaces	O
to	O
be	O
used	O
for	O
organizing	O
commands	O
and	O
variables	O
.	O
</s>
<s>
Itcl	B-Application
(	O
like	O
Tcl	B-Operating_System
)	O
has	O
built-in	O
support	O
for	O
the	O
integration	O
of	O
C	O
code	O
into	O
Itcl	B-Application
classes	O
.	O
</s>
<s>
Itcl	B-Application
follows	O
the	O
same	O
copyright	O
restrictions	O
as	O
Tcl/Tk	B-Application
.	O
</s>
