ENDIF: Terminate an IF THEN ELSEIF ELSE ENDIF construct

ENDIF must be the last statement in the IF THEN ELSEIF ELSE ENDIF construct.

• A block IF construct must end with an ENDIF statement

• IF( expression ) THEN
• ! statements executed if expression does NOT evaluate to zero
• ELSEIF( other_expression ) THEN
• ! statements executed if other_expression does NOT evaluate to zero
• ELSE
• ! statements executed in all other cases
• ENDIF