User:Maharba/Yttrium

=Work In Progress=

Yttrium is an esoteric programming language by Abraham Karplus. It has only one command, which copies a value from one register to another. For memory storage besides the registers, there are 10 unbounded tapes of integers, only accessible through certain registers.

A pound sign # begins a comment. All other characters are ignored; it is conventional to separate commands with commas.

Registers
All registers are initialized at 0, except that r starts at the result of function 0, which is 1.

m0 to m9 Address of current cell. v0 to v9 Value of current cell. i Reading gets a character from input; writing sends a character to output. f ID number of the operation. a and b Arguments for the operation. r Result of the operation. Read-only. j Jump.

Tapes
There are 10 tapes, numbered 0 through 9. Each is completely independent of the others. To specify the address on a specific tape, write to the m register for that tape. To read or write a cell value, use the v register for that tape, whose contents are those of the currently addressed cell.

Input and Output
Input and output are done by reading and writing register i. One character at a time is sent. End of file is represented by the value -1.

Operations
To use a built-in operation, the f register must contain the ID for that operation:

0 Always returns 1. 1 Addition. 2 Multiplication. 3 Negation (ignores second argument). 4 Division (rounds toward zero). 5 Boolean not (ignores second argument). 6 Boolean or.

The a and b registers contain the first and second arguments for the operation, and the r</tt> register becomes the result.

Jumps
To jump, write a number to the j</tt> register. This jumps forward (or backward, for a negative number) the written number of commands. Since the next command is normally selected after the current one finishes, a jump of 0 goes to the next command as normal, while a jump of 1 skips a command. To go to the command before the jump would require a jump of -2. Jumping outside of the program terminates it. When the jump register is read from, it always returns 0.

Cat
I have no idea if this works. r b, r f # change to addition r a, r a, r v3 # set v3 to 3 r a, r a, r v5 # set v5 to 5 r a, r a, r a, r a, r a, v3 f, r v9 # set v9 to -9 b f # change back to addition i v0, v0 i # input and output v0 a, r a, v5 f, r v1, b f # check for EOF v1 j, v9 j # repeat if not EOF

Truth machine
Ditto. r b, r f # change to addition r a, r v2 # set v2 to 2 r a, r v3 # set v3 to 3 v2 a, v3 f, r v9 # set v9 to -2 b f # change back to addition i a # get input a b, r j # jump 2 on '1' j i, v3 j # print '0' and exit f i, v9 j # print '1' and repeat