Acme::URM

Acme::URM is a Perl module that allows you to emulate an URM in Perl. It is an interesting tool to have because why not? URM is an abbreviation for unlimited register machine and it has an infinite number of registers such as R0, R1, etc. These registers contain natural numbers (r0, r1, etc.) and their default values are set to 0.

The URM can operate using one of the following instructions:

* Z(n) - sets up register with index n to zero
* S(n) - increments the value of the register with index n by 1
* T(m, n) - sets up the value of the register with index n to the value of the register with the index m
* J(m, n, q) - a conditional instruction that checks for equality between the values of registers with indexes m and n. If they are equal, it will go to instruction with index q (which is a zero-based index). Otherwise, it moves to the following instruction.

A URM program is a finite list of URM instructions. In order to use Acme::URM, you first need to use:

 use Acme::URM;

Then, you can create an object of the URM:

 my $rm = Acme::URM->new();

After that, you can create a program that summarizes the parameters given by R0 and R1:

$urm->program(
'T(0,2)',
'T(1,3)',
'J(3,4,6)',
'S(2)',
'S(4)',
'J(0,0,2)',
'T(0,3)',
'J(3,1,'.Acme::URM::LAST.')',
'J(3,2,11)',
'S(3)',
'J(0,0,7)',
'T(1,0)',
);

Next, you can fill the registers by using:

 $urm->register( 0, 2, 2 );

Finally, you can run the program and expect the result to be 4:

 my $res = $urm->run(); # res must be 4.

In conclusion, Acme::URM is a useful Perl module for emulating unlimited register machines in Perl. The usage explained above can give you a good understanding of how it works.