Bicep logical operators
The logical operators evaluate boolean values, return non-null values, or evaluate a conditional expression. To run the examples, use Azure CLI or Azure PowerShell to deploy a Bicep file.
Operator | Name |
---|---|
&& |
And |
|| |
Or |
! |
Not |
?? |
Coalesce |
? : |
Conditional expression |
operand1 && operand2
Determines if both values are true.
Operand | Type | Description |
---|---|---|
operand1 |
boolean | The first value to check if true. |
operand2 |
boolean | The second value to check if true. |
More operands | boolean | More operands can be included. |
True
when both values are true, otherwise false
is returned.
Evaluates a set of parameter values and a set of expressions.
param operand1 bool = true
param operand2 bool = true
output andResultParm bool = operand1 && operand2
output andResultExp bool = 10 >= 10 && 5 > 2
Output from the example:
Name | Type | Value |
---|---|---|
andResultParm |
boolean | true |
andResultExp |
boolean | true |
To avoid The language expression property 'foo' doesn't exist exception with Bicep objects, you can use the And logical operator as shown in the following example:
param objectToTest object = {
one: 1
two: 2
three: 3
}
output bar bool = contains(objectToTest, 'four') && objectToTest.four == 4
operand1 || operand2
Determines if either value is true.
Operand | Type | Description |
---|---|---|
operand1 |
boolean | The first value to check if true. |
operand2 |
boolean | The second value to check if true. |
More operands | boolean | More operands can be included. |
True
when either value is true, otherwise false
is returned.
Evaluates a set of parameter values and a set of expressions.
param operand1 bool = true
param operand2 bool = false
output orResultParm bool = operand1 || operand2
output orResultExp bool = 10 >= 10 || 5 < 2
Output from the example:
Name | Type | Value |
---|---|---|
orResultParm |
boolean | true |
orResultExp |
boolean | true |
To avoid The language expression property array index 'x' is out of bounds exception, you can use the Or logical operator as shown in the following example:
param emptyArray array = []
param numberArray array = [1, 2, 3]
output foo bool = empty(emptyArray) || emptyArray[0] == 'bar'
output bar bool = length(numberArray) >= 3 || numberArray[3] == 4
!boolValue
Negates a boolean value.
Operand | Type | Description |
---|---|---|
boolValue |
boolean | Boolean value that's negated. |
Negates the initial value and returns a boolean. If the initial value is true
, then false
is returned.
The not
operator negates a value. The values can be wrapped with parentheses.
param initTrue bool = true
param initFalse bool = false
output startedTrue bool = !(initTrue)
output startedFalse bool = !initFalse
Output from the example:
Name | Type | Value |
---|---|---|
startedTrue |
boolean | false |
startedFalse |
boolean | true |
operand1 ?? operand2
Returns first non-null value from operands.
Operand | Type | Description |
---|---|---|
operand1 |
string, integer, boolean, object, array | Value to test for null . |
operand2 |
string, integer, boolean, object, array | Value to test for null . |
More operands | string, integer, boolean, object, array | Value to test for null . |
Returns the first non-null value. Empty strings, empty arrays, and empty objects aren't null
and an <empty> value is returned.
The output statements return the non-null values. The output type must match the type in the comparison or an error is generated.
param myObject object = {
isnull1: null
isnull2: null
string: 'demoString'
emptystr: ''
integer: 10
}
output nonNullStr string = myObject.isnull1 ?? myObject.string ?? myObject.isnull2
output nonNullInt int = myObject.isnull1 ?? myObject.integer ?? myObject.isnull2
output nonNullEmpty string = myObject.isnull1 ?? myObject.emptystr ?? myObject.string ?? myObject.isnull2
Output from the example:
Name | Type | Value |
---|---|---|
nonNullStr |
string | demoString |
nonNullInt |
int | 10 |
nonNullEmpty |
string | <empty> |
condition ? true-value : false-value
Evaluates a condition and returns a value whether the condition is true or false.
Operand | Type | Description |
---|---|---|
condition |
boolean | Condition to evaluate as true or false. |
true-value |
string, integer, boolean, object, array | Value when condition is true. |
false-value |
string, integer, boolean, object, array | Value when condition is false. |
This example evaluates a parameter's initial and returns a value whether the condition is true or false.
param initValue bool = true
output outValue string = initValue ? 'true value' : 'false value'
Output from the example:
Name | Type | Value |
---|---|---|
outValue |
string | true value |
- To create a Bicep file, see Quickstart: Create Bicep files with Visual Studio Code.
- For information about how to resolve Bicep type errors, see Any function for Bicep.
- To compare syntax for Bicep and JSON, see Comparing JSON and Bicep for templates.
- For examples of Bicep functions, see Bicep functions.