"FRTH" Some common forth commands

Fingerprint ID:0x46525448

This fingerprint, from RC/Funge-98, implements common stack operations from Forth. It provides the following commands:

D : ... — ... size

Pushes the size of stack before execution. Same to 7y5*d+y.

L : ... n — ...

Pops n. Then moves (n+1)-th cell to the top if n is positive or moves the top to (-n+1)-th cell if negative. (For example, 123453L is same to 13452 and 1234503-L is same to 15234.) Assumes that the stack has infinite zeroes under the bottom if n is out of bound.

O : a b — a b a

Pushes second-to-the-top cell in the stack. Same to 1P.

P : ... n — ... value

Pushes (n+1)-th cell in the stack. Assumes that the stack has infinite zeroes under the bottom if n is out of bound. Reflects if n is negative.

R : a b c — b c a

Moves third-to-the-top cell to the top. Same to 2L.