<s>
Thue	B-Language
(	O
)	O
is	O
an	O
esoteric	O
programming	O
language	O
invented	O
by	O
John	O
Colagioia	O
in	O
early	O
2000	O
.	O
</s>
<s>
Because	O
it	O
is	O
able	O
to	O
define	O
languages	O
of	O
such	O
complexity	O
,	O
it	O
is	O
also	O
Turing-complete	B-Algorithm
itself	O
.	O
</s>
<s>
Thue	B-Language
is	O
based	O
on	O
a	O
nondeterministic	O
string	O
rewriting	O
system	O
called	O
semi-Thue	O
grammar	O
,	O
which	O
itself	O
is	O
named	O
after	O
the	O
Norwegian	O
mathematician	O
Axel	O
Thue	B-Language
.	O
</s>
<s>
The	O
author	O
describes	O
it	O
as	O
follows	O
:	O
"	O
Thue	B-Language
represents	O
one	O
of	O
the	O
simplest	O
possible	O
ways	O
to	O
construe	O
constraint-based	B-Application
programming	I-Application
.	O
</s>
<s>
It	O
is	O
to	O
the	O
constraint-based	O
paradigm	O
what	O
languages	O
like	O
OISC	B-Application
are	O
to	O
the	O
imperative	O
paradigm	O
;	O
in	O
other	O
words	O
,	O
it	O
's	O
a	O
tar	O
pit.	O
"	O
</s>
<s>
A	O
Thue	B-Language
program	O
starts	O
with	O
a	O
rulebase	O
,	O
which	O
is	O
a	O
series	O
of	O
substitution	O
rules	O
,	O
each	O
of	O
this	O
form	O
:	O
</s>
<s>
Thue	B-Language
consumes	O
the	O
initial	O
symbols	O
and	O
substitutes	O
the	O
result	O
of	O
the	O
rules	O
for	O
each	O
of	O
the	O
initial	O
state	O
's	O
symbols	O
.	O
</s>
<s>
Thue	B-Language
terminates	O
when	O
lhs	O
cannot	O
be	O
found	O
in	O
a	O
resultant	O
state	O
.	O
</s>
