NTFJ
Designed by  Conor O'Brien 

Appeared in  2016 
Memory system  stackbased 
Computational class  Unknown computational class 
Major implementations  Original, C implementation, Online interpreter 
File extension(s)  .ntfj 
NTFJ is a minimalist language created by User:Conor O'Brien. It originally had four commands: NAND, TRUE, FALSE, JUMP. These were the basis for its name. The language operates on a stack by manipulating bits and integers.
NTFJ has 13 commands:
Command  Name  Explanation 

 
NAND  Pops two values A and B and pushes A NAND B ; if A and B are both bits, it pushes 1(A&B) ; otherwise, it pushes 255(A&B) .

~ 
FALSE  Pushes 0 to the stack.

# 
TRUE  Pushes 1 to the stack.

^ 
JUMP  Pops n , jumps to the n th command.

@ 
BYTE  Pops eight values V1...V8 and pushes the number V1*(2^7) + ... + V8*(2^0) OR, if V1 > 1 , pushes the bits in that number.

( 
PEEK  If the top value of the stack is 0 , jumps to the next ) .

) 
ENDPEEK  Closes a ( command.

$ 
DROP  Drops the top value of the stack. 
: 
DUP  Duplicates the top value of the stack 
/ 
LENGTH  Pushes the number of items in the stack. 
{ 
ROTATE  Pops N ; shifts the stack and pushes it to the front N times.

} 
REV ROTATE  Pops N ; pops from the stack and unshifts it N times.

` 
DEBUG  Displays the program's state. 
The normal logical operators are representable in NTFJ:
 Logical negation is
:
:(A NAND A) = NOT (A AND A) = NOT A
.  Logical conjunction (and) is
:
:NOT (A NAND B) = NOT NOT (A AND B) = A AND B
.  Logical disjunction (or) is
:#}:#{
.#}
and#{
simply poke around the stack and focus onB
and A respectively.(NOT A) NAND (NOT B) = NOT ((NOT A) AND (NOT B)) = A OR B
.
Computation class
It is thought that NTFJ is Turing Complete, as it bears a remarkable resemblance to Etre.
Minification
One can begin to remove some commands from NTFJ. The following commands are superfluous ` *
.
#
is equivalent to ~~
, or 0 NAND 0
.
$
is equivalent to ~:
, which converts the top of the stack into 1
, then negates it into 0
, then NAND's the resulting value. A NAND 1 = A
, so the top value is ignored.
Thus, the following 9 commands are left:
 ~ ^ @ ( ) : { }
@
is needed to jump, and :
is needed to produce more values on the stack.