<s>
In	O
computer	B-General_Concept
science	I-General_Concept
,	O
implicit	B-Operating_System
parallelism	I-Operating_System
is	O
a	O
characteristic	O
of	O
a	O
programming	O
language	O
that	O
allows	O
a	O
compiler	B-Language
or	O
interpreter	B-Application
to	O
automatically	O
exploit	O
the	O
parallelism	B-Operating_System
inherent	O
to	O
the	O
computations	O
expressed	O
by	O
some	O
of	O
the	O
language	O
's	O
constructs	O
.	O
</s>
<s>
A	O
pure	O
implicitly	B-Operating_System
parallel	I-Operating_System
language	O
does	O
not	O
need	O
special	O
directives	O
,	O
operators	O
or	O
functions	O
to	O
enable	O
parallel	O
execution	O
,	O
as	O
opposed	O
to	O
explicit	O
parallelism	B-Operating_System
.	O
</s>
<s>
Programming	O
languages	O
with	O
implicit	B-Operating_System
parallelism	I-Operating_System
include	O
Axum	B-Language
,	O
BMDFM	B-Operating_System
,	O
HPF	B-Language
,	O
Id	B-Language
,	O
LabVIEW	B-Application
,	O
MATLAB	B-Language
M-code	I-Language
,	O
NESL	B-Language
,	O
SaC	B-Language
,	O
SISAL	B-Language
,	O
ZPL	B-Language
,	O
and	O
pH	O
.	O
</s>
<s>
If	O
a	O
particular	O
problem	O
involves	O
performing	O
the	O
same	O
operation	O
on	O
a	O
group	O
of	O
numbers	O
(	O
such	O
as	O
taking	O
the	O
sine	O
or	O
logarithm	O
of	O
each	O
in	O
turn	O
)	O
,	O
a	O
language	O
that	O
provides	O
implicit	B-Operating_System
parallelism	I-Operating_System
might	O
allow	O
the	O
programmer	O
to	O
write	O
the	O
instruction	O
thus	O
:	O
</s>
<s>
The	O
compiler	B-Language
or	O
interpreter	B-Application
can	O
calculate	O
the	O
sine	O
of	O
each	O
element	O
independently	O
,	O
spreading	O
the	O
effort	O
across	O
multiple	O
processors	O
if	O
available	O
.	O
</s>
<s>
A	O
programmer	O
that	O
writes	O
implicitly	B-Operating_System
parallel	I-Operating_System
code	O
does	O
not	O
need	O
to	O
worry	O
about	O
task	O
division	O
or	O
process	O
communication	O
,	O
focusing	O
instead	O
on	O
the	O
problem	O
that	O
his	O
or	O
her	O
program	O
is	O
intended	O
to	O
solve	O
.	O
</s>
<s>
Implicit	B-Operating_System
parallelism	I-Operating_System
generally	O
facilitates	O
the	O
design	O
of	O
parallel	B-Operating_System
programs	I-Operating_System
and	O
therefore	O
results	O
in	O
a	O
substantial	O
improvement	O
of	O
programmer	O
productivity	O
.	O
</s>
<s>
Many	O
of	O
the	O
constructs	O
necessary	O
to	O
support	O
this	O
also	O
add	O
simplicity	O
or	O
clarity	O
even	O
in	O
the	O
absence	O
of	O
actual	O
parallelism	B-Operating_System
.	O
</s>
<s>
The	O
example	O
above	O
,	O
of	O
list	B-Language
comprehension	I-Language
in	O
the	O
sin( )	O
function	O
,	O
is	O
a	O
useful	O
feature	O
in	O
of	O
itself	O
.	O
</s>
<s>
By	O
using	O
implicit	B-Operating_System
parallelism	I-Operating_System
,	O
languages	O
effectively	O
have	O
to	O
provide	O
such	O
useful	O
constructs	O
to	O
users	O
simply	O
to	O
support	O
required	O
functionality	O
(	O
a	O
language	O
without	O
a	O
decent	O
for	B-Language
loop	I-Language
,	O
for	O
example	O
,	O
is	O
one	O
few	O
programmers	O
will	O
use	O
)	O
.	O
</s>
<s>
Languages	O
with	O
implicit	B-Operating_System
parallelism	I-Operating_System
reduce	O
the	O
control	O
that	O
the	O
programmer	O
has	O
over	O
the	O
parallel	O
execution	O
of	O
the	O
program	O
,	O
resulting	O
sometimes	O
in	O
less-than-optimal	O
parallel	B-Operating_System
efficiency	I-Operating_System
.	O
</s>
<s>
The	O
makers	O
of	O
the	O
Oz	B-Language
programming	I-Language
language	I-Language
also	O
note	O
that	O
their	O
early	O
experiments	O
with	O
implicit	B-Operating_System
parallelism	I-Operating_System
showed	O
that	O
implicit	B-Operating_System
parallelism	I-Operating_System
made	O
debugging	O
difficult	O
and	O
object	O
models	O
unnecessarily	O
awkward	O
.	O
</s>
<s>
If	O
implicit	B-Operating_System
parallelism	I-Operating_System
is	O
desired	O
,	O
this	O
creates	O
a	O
new	O
requirement	O
for	O
constructs	O
and	O
keywords	O
to	O
support	O
code	O
that	O
cannot	O
be	O
threaded	O
or	O
distributed	O
.	O
</s>
