<s>
Dependent	B-Language
ML	I-Language
is	O
an	O
experimental	O
functional	B-Language
programming	I-Language
language	I-Language
proposed	O
by	O
Hongwei	O
Xi	O
and	O
Frank	O
Pfenning	O
.	O
</s>
<s>
Dependent	B-Language
ML	I-Language
extends	O
ML	B-Language
by	O
a	O
restricted	O
notion	O
of	O
dependent	O
types	O
:	O
types	O
may	O
be	O
dependent	O
on	O
static	O
indices	O
of	O
type	O
Nat	O
(	O
natural	O
numbers	O
)	O
.	O
</s>
<s>
Dependent	B-Language
ML	I-Language
employs	O
a	O
constraint	O
theorem	O
prover	O
to	O
decide	O
a	O
strong	O
equational	O
theory	O
over	O
the	O
index	O
expressions	O
.	O
</s>
<s>
Dependent	B-Language
ML	I-Language
has	O
been	O
superseded	O
by	O
ATS	B-Language
and	O
is	O
no	O
longer	O
under	O
active	O
development	O
.	O
</s>
