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{{fbdoc item="title" value="Operator ORELSE (Short Circuit Inclusive Disjunction)"}}----
Returns the short circuit-or (Inclusive Disjunction) of two numeric values

{{fbdoc item="syntax"}}##
[[KeyPgDeclare|declare]] [[KeyPgOperator|operator]] **""OrElse""** ( [[KeyPgByref|byref]] //lhs// [[KeyPgAs|as]] //T1//, [[KeyPgByref|byref]] //rhs// [[KeyPgAs|as]] //T2// ) [[KeyPgAs|as]] //Ret//
##
{{fbdoc item="usage"}}##
//result// = //lhs// **""OrElse""** //rhs//
##
{{fbdoc item="param"}}
##//lhs//##
The left-hand side expression.
##//T1//##
Any numeric or boolean type.
##//rhs//##
The right-hand side expression.
##//T2//##
Any numeric or boolean type.
##//Ret//##
A numeric or boolean type (varies with ##//T1//## and ##//T2//##).

{{fbdoc item="ret"}}
Returns the short circuit-or (inclusive disjunction) of the two operands.

{{fbdoc item="desc"}}
This operator evaluates the left hand side expression. If the result is nonzero, then ##-1## (true) is immediately returned. If the result is zero then the right hand side is evaluated, and the logical result from that is returned, returning ##-1## (true) for a nonzero value or ##0## (false) for zero.
(for conversion of a boolean to an integer, false or true boolean value becomes 0 or -1 integer value)

The truth table below demonstrates all combinations of a short circuit-or operation, the '-' denotes that the operand is not evaluated.

{{table columns="3" cellpadding="2" cells="Lhs Value;Rhs Value;Result;0;0;0;0;nonzero;-1;nonzero;-;-1"}}

Short-circuiting is performed - only expressions needed to calculate the result are evaluated. The left hand side ##//lhs//## is evaluated first, and only if it evaluates to zero (false) is the right hand side ##//rhs//## also evaluated. If the left hand side evaluation ##//lhs//## returns non-zero (true), it is known that at that point that the overall condition is true, so the right hand side ##//rhs//## is not evaluated (skipped).

The return type is almost always an ##[[KeyPgInteger|Integer]]##, of the value ##0## or ##-1##, denoting false and true respectively. Except if the left and right-hand side types are both ##[[KeyPgBoolean|Boolean]]##, then the return type is also ##[[KeyPgBoolean|Boolean]]##.

This operator cannot be overloaded for user-defined types.

{{fbdoc item="ex"}}
{{fbdoc item="filename" value="examples/manual/operator/orelse.bas"}}%%(freebasic)
' Using the ORELSE operator on two numeric values
DIM AS INTEGER numeric_value1, numeric_value2
numeric_value1 = 15
numeric_value2 = 30

'Result = -1
PRINT numeric_value1 ORELSE numeric_value2
SLEEP
%%

{{fbdoc item="diff"}}
- This operator was not available in QB.

{{fbdoc item="see"}}
- ##[[KeyPgOpAndAlso|AndAlso]]##
- ##[[KeyPgOpOr|Or]]##
- [[TblTruth|Operator Truth Tables]]

{{fbdoc item="back" value="CatPgOpShortCircuit|Short Circuit Operators"}}{{fbdoc item="back" value="CatPgOperators|Operators"}}
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