How to elegantly combine a guard statement with a condition?

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I currently have the guard statement:

 guard let designationQuota = Defaults.quotas.value?.designationQuota, designationQuota > 0 else {
      return AppDelegate.shared.presentNoDesignationQuotaWarning()
 }

however I only want to do the guard block if the variable needsQuota == true. I want to skip the guard statement if needsQuota == false. Is there a nicer way of doing this over than an if statement with a return?

EDIT:

How do I simplify this into a single guard?

if needsQuota {
  guard let designationQuota = Defaults.quotas.value?.designationQuota, designationQuota > 0 else {
      return AppDelegate.shared.presentNoDesignationQuotaWarning()
   }
}
3

There are 3 best solutions below

1
ielyamani On

How about :

guard !needsQuota ||
    (Defaults.quotas.value?.designationQuota.map { $0 > 0 } == true) else {
    return AppDelegate.shared.presentNoDesignationQuotaWarning()
}
0
Dávid Pásztor On

The problem is that you want to continue execution differently in case your if condition fails or in case your guard fails, so you cannot really combine them into a single guard. However, you could combine the two conditions into an if statement by putting the negated version of your guard condition in the if statement.

if needsQuota && (Defaults.quotas.value?.designationQuota ?? 0 <= 0) {
    return AppDelegate.shared.presentNoDesignationQuotaWarning()
}
0
henrik-dmg On

Wouldn‘t this do the trick?

guard needsQuota, let designationQuota = Defaults.quotas.value?.designationQuota, designationQuota > 0 else {
    return AppDelegate.shared.presentNoDesignationQuotaWarning()
}