<s>
TaskJuggler	B-Language
is	O
GPL-licensed	O
(	O
free	B-Application
software	I-Application
)	O
project	B-Application
management	I-Application
software	I-Application
that	O
runs	O
under	O
the	O
Linux	B-Application
and	O
Unix	B-Application
operating	I-Application
systems	I-Application
and	O
is	O
programmed	O
in	O
C++	B-Language
using	O
the	O
Qt	B-Language
toolkit	I-Language
and	O
KDE	B-Application
libraries	O
.	O
</s>
<s>
The	O
TaskJuggler	B-Language
Project	O
was	O
started	O
in	O
2001	O
by	O
Chris	O
Schläger	O
.	O
</s>
<s>
Early	O
releases	O
provided	O
a	O
command	B-Application
line	I-Application
tool	I-Application
that	O
generated	O
HTML	O
reports	O
.	O
</s>
<s>
From	O
August	O
2005	O
to	O
July	O
2010	O
,	O
the	O
package	O
also	O
provided	O
a	O
graphical	O
user	O
interface	O
based	O
on	O
the	O
KDE	B-Application
libraries	O
.	O
</s>
<s>
TaskJuggler	B-Language
III	O
was	O
released	O
on	O
5	O
July	O
2010	O
.	O
</s>
<s>
It	O
is	O
a	O
completely	O
re-implemented	O
version	O
of	O
the	O
TaskJuggler	B-Language
2.x	O
series	O
and	O
written	O
in	O
Ruby	B-Language
.	O
</s>
<s>
The	O
graphical	O
user	O
interface	O
from	O
the	O
2.x	O
version	O
has	O
not	O
yet	O
been	O
ported	O
to	O
TaskJuggler	B-Language
III	O
;	O
TaskJuggler	B-Language
III	O
documents	O
,	O
which	O
are	O
plain	O
text	O
files	O
,	O
are	O
edited	O
with	O
a	O
text	O
editor	O
and	O
processed	O
on	O
the	O
command	B-Application
line	I-Application
.	O
</s>
<s>
A	O
TaskJuggler	B-Language
project	O
consists	O
of	O
one	O
or	O
more	O
plain	O
text	O
documents	O
written	O
in	O
a	O
domain-specific	B-Language
declarative	B-Language
programming	I-Language
language	I-Language
.	O
</s>
<s>
The	O
documents	O
consist	O
of	O
a	O
root	O
project	O
file	O
and	O
optional	O
sub-files	O
incorporated	O
into	O
the	O
root	O
by	O
means	O
of	O
the	O
include	O
keyword	O
(	O
property	O
in	O
TaskJuggler	B-Language
lingo	O
)	O
,	O
to	O
one	O
or	O
more	O
levels	O
.	O
</s>
<s>
The	O
TaskJuggler	B-Language
language	O
reference	O
refers	O
to	O
the	O
project	O
definition	O
source	O
document	O
somewhat	O
loosely	O
as	O
The	O
TJP	O
File	O
.	O
</s>
<s>
The	O
TJP	O
is	O
a	O
declarative	B-Language
document	O
.	O
</s>
<s>
TaskJuggler	B-Language
functions	O
as	O
a	O
report	O
compilation	O
tool	O
.	O
</s>
<s>
After	O
TJP	O
program	O
is	O
written	O
,	O
reports	O
on	O
the	O
state	O
of	O
the	O
project	O
are	O
generated	O
by	O
running	O
the	O
TaskJuggler	B-Language
compiler	O
on	O
the	O
program	O
.	O
</s>
<s>
The	O
TJP	O
compiler	O
includes	O
a	O
scheduling	O
component	O
based	O
on	O
a	O
heuristic	B-Algorithm
algorithm	I-Algorithm
.	O
</s>
<s>
TaskJuggler	B-Language
is	O
able	O
to	O
generate	O
a	O
wide	O
variety	O
of	O
reports	O
including	O
Gantt	B-Application
based	O
on	O
report	O
declarations	O
within	O
the	O
TJP	O
.	O
</s>
<s>
The	O
TaskJuggler	B-Language
compiler	O
is	O
able	O
to	O
handle	O
large	O
projects	O
with	O
over	O
10,000	O
tasks	O
,	O
1000	O
resources	O
,	O
and	O
complex	O
constraints	O
.	O
</s>
<s>
A	O
common	O
feature	O
of	O
compilation	O
tools	O
shared	O
by	O
TaskJuggler	B-Language
is	O
that	O
future	O
compilations	O
(	O
reports	O
)	O
do	O
not	O
necessarily	O
reflect	O
past	O
outputs	O
,	O
even	O
where	O
the	O
inputs	O
are	O
extremely	O
similar	O
.	O
</s>
<s>
TaskJuggler	B-Language
presently	O
contains	O
(	O
as	O
of	O
version	O
2.3.0	O
)	O
no	O
provision	O
for	O
generating	O
a	O
minimal	O
schedule	O
change	O
from	O
an	O
existing	O
schedule	O
projection	O
based	O
on	O
a	O
hypothetical	O
input	O
,	O
such	O
as	O
"	O
what	O
if	O
I	O
assign	O
Bob	O
for	O
four	O
hours	O
to	O
the	O
documentation	O
task	O
?	O
"	O
.	O
</s>
<s>
Iterative	O
constraint	O
refinement	O
is	O
a	O
powerful	O
technique	O
,	O
but	O
lacks	O
the	O
immediacy	O
of	O
incremental	O
recalculation	O
in	O
a	O
spreadsheet	B-Application
when	O
used	O
in	O
a	O
similar	O
capacity	O
as	O
a	O
financial	O
projection	O
tool	O
.	O
</s>
<s>
The	O
TaskJuggler	B-Language
design	O
frees	O
the	O
project	O
manager	O
to	O
focus	O
on	O
information	O
that	O
is	O
known	O
about	O
the	O
project	O
at	O
any	O
stage	O
of	O
the	O
project	O
.	O
</s>
<s>
TaskJuggler	B-Language
then	O
turns	O
this	O
information	O
into	O
meaningful	O
reports	O
and	O
charts	O
.	O
</s>
<s>
The	O
textual	O
project	O
description	O
sets	O
TaskJuggler	B-Language
apart	O
from	O
other	O
project	O
management	O
programs	O
.	O
</s>
<s>
Based	O
on	O
the	O
provided	O
constraints	O
TaskJuggler	B-Language
computes	O
a	O
schedule	O
for	O
the	O
given	O
task	O
items	O
.	O
</s>
<s>
TaskJuggler	B-Language
computes	O
task	O
intervals	O
,	O
allocation	O
times	O
for	O
every	O
resource	O
,	O
and	O
a	O
profit/loss	O
analysis	O
for	O
the	O
project	O
.	O
</s>
<s>
The	O
plain	O
text	O
project	O
description	O
is	O
written	O
in	O
a	O
hierarchical	O
,	O
declarative	B-Language
programming	I-Language
language	I-Language
that	O
requires	O
one	O
to	O
think	O
abstractly	O
about	O
the	O
sequencing	O
and	O
constraints	O
in	O
the	O
project	O
,	O
as	O
well	O
as	O
the	O
structure	O
of	O
the	O
program	O
itself	O
.	O
</s>
<s>
While	O
powerful	O
,	O
this	O
complexity	O
can	O
lead	O
to	O
a	O
steep	O
learning	O
curve	O
for	O
gaining	O
proficiency	O
in	O
the	O
use	O
of	O
TaskJuggler	B-Language
.	O
</s>
