The operation of bitwise integer logical OR between two items. The two operands are internally converted to 4 byte integers before the OR operation.
IF A=2 OR B=3 THEN 110 X=B OR 4
You can leave out the space between OR and a preceding constant, but it makes your programs difficult to read.
You can use OR as a logical operator or as a 'bit-by-bit' (bitwise) operator. The operands can be boolean (logical) or numeric.
Unfortunately, BBC BASIC does not have true Boolean variables; it uses numeric variables and assigns the value 0 for FALSE and -1 for TRUE. This can lead to confusion at times. (See NOT for more details).
In the example below, the operands are Boolean (logical). In other words, the result of the tests (IF) A=2 and (IF) B=3 is either TRUE or FALSE. The result of this example will be TRUE if A=2 or B=3.
answer=(A=2 OR B=3)
The brackets are not necessary, they have been included to make the example easier to follow.
The last example, uses the OR in a similar fashion to the numeric operators (+, -, etc).
Suppose X was -20 in the following example,
A=X OR 11
the OR operation would be:
11111111 11111111 11111111 11101100 00000000 00000000 00000000 00001011 11111111 11111111 11111111 11101111 = -17
<n-var>=<numeric> OR <numeric>