Boolean Expressions
A boolean expression is an expression which eventually evaluates to either True or False. These are used as conditions inside Flow Control statements. A boolean expression is built using the following: > Greater than >= Greater than or equal to < Less than <= Less than or equal to = Equal to <> Not equal to These are used inside the flow control conditions e.g. if a<b ... end if Combining Boolean Expressions
Boolean expressions can also be combined in the following ways... if a<b and c<d ... end if In this example, the boolean expression only evaluates to true if a is less than b AND c is less than d. if a<b or c<d ... end if In this example, the boolean expression only evaluates to true if a is less than b OR c is less than d. A not operator is also available... if not a=b ... end if This boolean expression only evaluates to true if a DOES NOT equal b. The not operator reverses the true/false value of a boolean expression. Numeric expressions as booleans
Numeric expressions can also be placed inside conditions. They are evaluated like this: 0 - False not 0 - True e.g. if a ... end if The body of the code will be executed as long as a does not equal 0.
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