Topic       : The GFA-Basic Compendium
Author      : GFA Systemtechnik GmbH
Version     : GFABasic.HYP v2.98 (12/31/2023)
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View Ref-FileAND, OR, XOR
NOT, IMP, EQV

These logical operators work at the bit level for 32-bit integer values.
Logical operators link two logical expressions and produce a logical result
(TRUE or FALSE). The operator NOT is an exception, in that it negates the value
of a given expression.

The numerical value for FALSE is 0, and for TRUE is -1.

For those interested in why these values should be chosen, the reason is that
TRUE is considered to be all ones in a 32-bit integer, and FALSE to be all
zeros. Thus:

    11111111111111111111111111111111 = TRUE

and

    00000000000000000000000000000000 = FALSE

Those familiar with two's complement arithmetic will recognize that the former
is the two's complement notation for -1.

All logical operators can also be applied to numerical expressions. In this
case the logical operations are implemented bit by bit. The effects of logical
operators will be described with so-called truth tables. In these tables the
logical values of the linked expressions are given in the first columns, and
the result in the last column.