The convert-x-y in the snake section of this tutorial consists of an incorrect implementation. The faulty implementation works as the cells word multiples the top-of-stack value by a scalar 1. However, in other forth runtimes, such as gforth, one cell takes 4 or 8 bytes, depending on the CPU word length.
The correct implementation should be : convert-x-y ( x y -- offset ) 24 * + cells ;
The
convert-x-yin thesnakesection of this tutorial consists of an incorrect implementation. The faulty implementation works as thecellsword multiples the top-of-stack value by a scalar 1. However, in other forth runtimes, such asgforth, one cell takes 4 or 8 bytes, depending on the CPU word length.The correct implementation should be
: convert-x-y ( x y -- offset ) 24 * + cells ;