<s>
Open	B-Language
Power	I-Language
Template	I-Language
is	O
a	O
web	B-Application
template	I-Application
engine	I-Application
written	O
in	O
PHP	B-Application
5	O
.	O
</s>
<s>
A	O
common	O
strategy	O
in	O
designing	O
web	B-Application
application	I-Application
is	O
separation	O
of	O
the	O
application	O
logic	O
(	O
i.e.	O
</s>
<s>
OPT	O
uses	O
a	O
dedicated	O
XML	B-Protocol
template	O
language	O
for	O
writing	O
templates	O
.	O
</s>
<s>
It	O
is	O
not	O
a	O
general-purpose	O
,	O
but	O
a	O
domain-specific	B-Language
language	I-Language
.	O
</s>
<s>
It	O
was	O
primarily	O
designed	O
to	O
support	O
and	O
simplify	O
template-specific	O
problems	O
with	O
a	O
set	O
of	O
declarative	B-Language
instructions	O
.	O
</s>
<s>
Instead	O
of	O
implementing	O
the	O
rendering	O
algorithms	O
and	O
statements	O
,	O
like	O
in	O
imperative	B-Application
programming	I-Application
,	O
the	O
template	O
designer	O
specifies	O
the	O
expected	O
result	O
and	O
features	O
.	O
</s>
<s>
The	O
library	O
provides	O
an	O
object-oriented	B-Language
API	B-General_Concept
based	O
on	O
the	O
solutions	O
from	O
popular	O
frameworks	O
.	O
</s>
<s>
The	O
project	O
started	O
in	O
November	O
2004	O
,	O
as	O
a	O
template	B-Application
engine	I-Application
for	O
a	O
discussion	O
board	O
project	O
inspired	O
by	O
Smarty	B-Language
.	O
</s>
<s>
It	O
offered	O
a	O
template	O
language	O
with	O
Smarty-like	O
syntax	O
and	O
a	O
small	O
set	O
of	O
declarative	B-Language
instructions	O
.	O
</s>
<s>
In	O
January	O
2008	O
,	O
the	O
developers	O
form	B-General_Concept
an	O
open-source	O
programming	O
team	O
,	O
Invenzzia	O
to	O
develop	O
OPT	O
and	O
other	O
PHP	B-Application
projects	O
.	O
</s>
<s>
At	O
the	O
same	O
time	O
,	O
the	O
development	O
of	O
Open	B-Language
Power	I-Language
Template	I-Language
2.0	O
began	O
.	O
</s>
<s>
The	O
OPT	O
2.0	O
template	O
language	O
is	O
an	O
XML	B-Protocol
application	O
and	O
allows	O
to	O
manipulate	O
the	O
XHTML	O
document	O
structure	O
.	O
</s>
<s>
XML	B-Protocol
manipulation	O
instructions	O
.	O
</s>
<s>
Imperative	B-Application
control	O
structures	O
:	O
conditions	O
and	O
loops	O
.	O
</s>
<s>
Expression	O
language	O
optimized	O
for	O
XML	B-Protocol
and	O
an	O
abstraction	O
layer	O
making	O
it	O
independent	O
from	O
PHP	B-Application
data	O
types	O
and	O
application-specific	O
implementation	O
details	O
(	O
data	O
formats	O
)	O
.	O
</s>
<s>
The	O
built-in	O
XML	B-Protocol
parser	I-Protocol
can	O
be	O
reconfigured	O
to	O
parse	O
certain	O
HTML	O
documents	O
or	O
plain	O
text	O
content	O
.	O
</s>
<s>
The	O
first	O
one	O
contains	O
the	O
presentation	O
code	O
as	O
an	O
XML	B-Protocol
template	O
:	O
</s>
