Azure Bicep nullability operators explained blog

coalesce.bicep

param parName string?
param parLocation string = resourceGroup().location

resource keyVault 'Microsoft.KeyVault/vaults@2023-07-01' = {
  name: parName ?? 'fallback-kv-name'
  location: parLocation
  properties: {
    enabledForDeployment: true
    enabledForTemplateDeployment: true
    enabledForDiskEncryption: true
    tenantId: tenant().tenantId
    sku: {
      name: 'standard'
      family: 'A'
    }
  }
}