VarStack

Not to be confused with Varstak.

VarStack is an esolang by User:ChuckEsoteric08 where all variables are 1-character stacks.

Specification

Commands look like this:

X;Y;Z

Declare label X, execute command Y and jump to label Z. If you are trying to access non-existing label, stack element, or stack itself then program will halt.

@X:Y	Create new stack called X with initial element(s) Y
$X:Y	Push X to stack Y.
!X	Pop element from stack X and discard it
"X	Output X
'X	Output stack X
?X	Ask for input and push it to stack X
#X=Y:Z	If top of the stack X is equal to Y jump to label Z
!X=Y:Z	If top of the stack X is not equal to Y jump to label Z
%X=Y:Z	If top of the stack X is equal top of the stack Y jump to label Z
~X	Swap top two elements in stack X
&X	Reverse stack X
^X	Move top of the stack X to the bottom

Examples

Hello, World!

hello;"Hello, World!;halt

Truth-machine

start;@X:0;input
input;?X;if
if;#X=0:print0;print1
print1;"1;print1
print0;"0;halt

Bitwise Cyclic Tag interpreter

You should input program by character. Then input @ and input data. After you inputed data input @ again.

initprogram;@code:0;initprogramfinish
initprogramfinish;!code;initdata
initdata;@data:0;initdatafinish
initdatafinish;!data;inputcode1
inputcode1;?code;inputcode2
inputcode2;#code=@:inputcode3;inputcode1
inputcode3;!code;inputcode4
inputcode4;&code;inputdata1
inputdata1;?data;inputdata2
inputdata2;#data=@:inputdata3;inputdata1
inputdata3;!data;inputdata4
inputdata4;&data;interpret
interpret;#code=0:remove;if1
remove;!data;move
if1;#data=1:nextinstruction;move
nextinstruction;^code;reverse
reverse;&data;enq
enq;#code=0:enq0;enq1
enq0;$0:data;endenq
enq1;$1:data;endenq
endenq;&data;interpret
move;^code;interpret

Cat Program

A perpetually repeating cat program is demonstrated in the following:

createStack;@X:;requestInput
requestInput;?X;printInput
printInput;'X;removeInput
removeInput;!X;requestInput

Interpreter

• Common Lisp implementation of the VarStack programming language.