Keyword Or

The logical Or operator.

Syntax

[If] expression Or expression [... ]

Description

Or is a logical operator which compares two expressions, or operands, and evaluates as True if either expression is True.

Multiple Or comparisons may be performed on a single line to compare more than two expressions.

Evaluation is performed from left to right and the operation immediately returns True (a behaviour known as 'early out') on encountering a True comparison; this means that no further comparisons on the line will be evaluated.

See also

And | Not
Language reference

Example

The example below demonstrates a simple comparison of two values.

Local a:Int = 0 
Local b:Int = 1 
 
If a Or b 
    Print "At least one of the operands evaluates as True" 
Else 
    Print "Neither operand evaluates as True" 
Endif 

The runnable example below demonstrates that although apples and pears are both zero, the line as a whole evaluates as True because the function ComplexOperation returns True; as long as one expression is True, the entire line is considered True.

Note that if you change apples or pears to a non-zero value, ComplexOperation is not called; this is due to the 'early-out' behaviour of the Or operator, which considers the entire line to be True as soon as any of the individual expressions evaluates as True.

Function Main () 
 
    Local apples:Int = 0 
    Local pears:Int = 0 
     
    If apples Or pears Or ComplexOperation () 
        Print "One or more expression was True" 
    Else 
        Print "None of the expressions were True" 
    Endif 
 
End 
 
Function ComplexOperation () 
    Print "Performing complex operation..." 
    Print "Ooh, this is really difficult..." 
    Print "Processor about to catch fire..." 
    Print "Etc..." 
    Return True 
End