Ada Programming/Keywords/or

Keywords or __TOC__ Logical operator Boolean operator X : Boolean := A < 10 or A > 20; Boolean shortcut operator In the below example the function G is only called when F(X) returns the value False. if F(X) or else G(Y) then Walk_The_Dog; end if; This shortcut operator is sometimes used to speed up the evaluation of boolean expressions, but the Ada Style Guide recommends to compare the performance of both forms before switching one to the other. In general, it is good idea to use or else in sake of performance only when the second expression involves a function call. The or else form is also used when the second expression is known to raise an exception unless the first expression is False. Unlike C/C++, Ada short-cut operators are not the standard way to evaluate boolean expressions. This is because Ada is designed to do by default what is generally safer, but lets the programmer request a different behaviour. Boolean operator on arrays The or operator is applied to each pair of boolean elements from the left and right arrays. The result has the same bounds as the left operand. type Day_Of_Month is range 1 .. 31; type Month_Array is array (Day_Of_Month) of Boolean; X : Month_Array := Function_1; Y : Month_Array := Function_2; Z : Month_Array := X or Y; Bitwise operator The operator or could be used with modular types to perform bitwise operations. Select statement alternative See Ada Programming/Tasking#Selective waiting. delay See Ada Programming/Tasking#Timeout. See also Wikibook Ada Programming Ada Programming/Keywords Ada Programming/Operators Ada 95 Reference Manual 2 9 Reserved Words 4 4 Expressions 4 5 1 Logical Operators and Short-circuit Control Forms P (informative) Syntax Summary Ada 2005 Reference Manual 2 9 Reserved Words 4 4 Expressions 4 5 1 Logical Operators and Short-circuit Control Forms P (informative) Syntax Summary Ada Quality and Style Guide 3 1 3 Capitalization 5 5 5 Short Circuit Forms of the Logical Operators 10 5 2 Short-Circuit Operators 10 6 3 Bit Operations on Modular Types Or