Difference Between If Let And Guard Let?

Ans : 

Basic Difference :

Guard let 

Early exist process from the scope
Require score existing like return, Throw etc.
Create a new variable those can be access out the scope.

if let 

Can not access out the scope.
no need to return statement. But we can write

Note : Both are used to unwrapped the Optional variable.


Guard let

• A guard statement is used to transfer program control out of a scope if one or more conditions aren’t met. 
• The value of any condition in a guard statement must be of type Bool or a type bridged to Bool. The condition can also be an optional binding declaration.

guard condition else { //Generally return }

func submit() {

guard let name = nameField.text else {

    show("No name to submit")

    return

}

If let

• Also popular as optional binding 
• For accessing optional object we use if let

if let roomCount = optionalValue {

        print("roomCount available")

} else {

       print("roomCount is nil")

}

Q. return is mandatory in guard let statement ?
A. Exit is mandatory in guard let statement. So return or throw is mandatory in guard let. Otherwise it gives compile time error.