<s>
Ceylon	B-Language
is	O
an	O
object-oriented	B-Language
,	O
strongly	O
statically	O
typed	O
programming	O
language	O
with	O
an	O
emphasis	O
on	O
immutability	B-Application
,	O
created	O
by	O
Red	O
Hat	O
.	O
</s>
<s>
Ceylon	B-Language
programs	O
run	O
on	O
the	O
Java	B-Language
virtual	I-Language
machine	I-Language
(	O
JVM	B-Language
)	O
,	O
and	O
could	O
be	O
compiled	O
to	O
JavaScript	B-Language
.	O
</s>
<s>
The	O
language	O
design	O
focuses	O
on	O
source	O
code	O
readability	O
,	O
predictability	O
,	O
toolability	B-Application
,	O
modularity	B-Architecture
,	O
and	O
metaprogrammability	B-Application
.	O
</s>
<s>
Important	O
features	O
of	O
Ceylon	B-Language
include	O
:	O
</s>
<s>
The	O
name	O
"	O
Ceylon	B-Language
"	O
is	O
an	O
oblique	O
reference	O
to	O
Java	B-Language
,	O
in	O
that	O
Java	B-Language
and	O
Sri	O
Lanka	O
,	O
formerly	O
known	O
as	O
Ceylon	B-Language
,	O
are	O
islands	O
known	O
for	O
growth	O
and	O
export	O
of	O
coffee	O
and	O
tea	O
.	O
</s>
<s>
In	O
August	O
2017	O
,	O
Ceylon	B-Language
was	O
donated	O
to	O
the	B-Application
Eclipse	I-Application
Foundation	I-Application
.	O
</s>
<s>
At	O
that	O
time	O
Ceylon	B-Language
's	O
development	O
got	O
arrested	O
.	O
</s>
<s>
Ceylon	B-Language
is	O
heavily	O
influenced	O
by	O
Java	B-Language
's	O
syntax	O
,	O
but	O
adds	O
many	O
new	O
features	O
.	O
</s>
<s>
One	O
of	O
the	O
most	O
novel	O
aspects	O
of	O
Ceylon	B-Language
compared	O
to	O
Java	B-Language
is	O
its	O
type	O
system	O
.	O
</s>
<s>
Ceylon	B-Language
foregoes	O
Java	B-Language
's	O
primitive	O
types	O
and	O
boxing	O
in	O
favor	O
of	O
a	O
type	O
system	O
composed	O
entirely	O
of	O
first-class	O
objects	O
.	O
</s>
<s>
Ceylon	B-Language
allows	O
for	O
union	O
and	O
intersection	O
types	O
,	O
in	O
a	O
similar	O
fashion	O
to	O
TypeScript	B-Language
,	O
Whiley	B-Language
and	O
Flow	O
.	O
</s>
<s>
The	O
following	O
example	O
shows	O
a	O
Ceylon	B-Language
function	O
which	O
may	O
take	O
either	O
an	O
integer	O
or	O
a	O
string	O
:	O
</s>
<s>
Union	O
and	O
intersection	O
types	O
are	O
used	O
to	O
provide	O
null	B-Application
safety	I-Application
.	O
</s>
<s>
The	O
top	O
type	O
of	O
the	O
Ceylon	B-Language
type	O
hierarchy	O
is	O
the	O
class	O
Anything	O
,	O
</s>
<s>
Similar	O
to	O
Java	B-Language
and	O
many	O
other	O
languages	O
,	O
and	O
with	O
a	O
similar	O
mechanism	O
as	O
algebraic	O
types	O
,	O
Ceylon	B-Language
supports	O
enumerated	B-Language
types	I-Language
,	O
otherwise	O
known	O
as	O
enums	B-Language
.	O
</s>
<s>
This	O
is	O
implemented	O
in	O
Ceylon	B-Language
with	O
a	O
pattern	O
of	O
limiting	O
the	O
instances	O
of	O
an	O
abstract	O
class	O
at	O
declaration	O
to	O
a	O
limited	O
set	O
of	O
objects	O
(	O
in	O
this	O
case	O
,	O
singleton	O
instances	O
)	O
.	O
</s>
<s>
Another	O
way	O
to	O
implement	O
this	O
pattern	O
is	O
with	O
the	O
new	O
constructor	O
feature	O
in	O
Ceylon	B-Language
1.2	O
where	O
the	O
objects	O
are	O
implemented	O
as	O
different	O
named	O
constructor	O
declarations	O
.	O
</s>
<s>
Ceylon	B-Language
is	O
strongly	O
and	O
statically	O
typed	O
,	O
but	O
also	O
has	O
support	O
for	O
type	O
inference	O
.	O
</s>
<s>
By	O
default	O
the	O
starter	O
(	O
ceylon	B-Language
run	O
)	O
runs	O
the	O
shared	O
run( )	O
function	O
of	O
a	O
module	B-Architecture
:	O
</s>
<s>
Versions	O
of	O
Ceylon	B-Language
released	O
:	O
</s>
<s>
All	O
parts	O
of	O
Ceylon	B-Language
are	O
available	O
as	O
free	B-Application
software	I-Application
,	O
mostly	O
the	O
Apache	B-Application
License	I-Application
.	O
</s>
