What will be the output of the following Swift code:

struct s1Struct {
var abc = "Hello"

func change() {
abc = "bye"
}
}

var a = s1Struct()
a.change()
print(a.abc)

Question

What will be the output of the following Swift code:

struct s1Struct {
 var abc = "Hello"
 
 func change() {
 abc = "bye"
 }
}

var a = s1Struct()
a.change()
print(a.abc)

Accepted Answer

The output will be 'bye'.

The code defines a struct 's1Struct' with a property 'abc' initialized to 'Hello'.
It also has a method 'change()' that changes the value of 'abc' to 'bye'.
An instance 'a' of 's1Struct' is created and its 'change()' method is called.
Finally, the value of 'abc' in the instance 'a' is printed, which will be 'bye'.

Accepted Answer

s1Struct is a struct, and abc is a variable property (var).
The change() method tries to modify abc, but it's declared as a func, which is not allowed to mutate the struct's properties by default.
In Swift, to mutate properties inside a struct's method, the method must be marked with the **mutating** keyword.
a = s1Struct() creates a new instance, so abc gets its default value "Hello".
The previous change to abc is discarded because the old instance is replaced.
Structs are value types, so assigning a new struct to a completely replaces the previous one.

What will be the output of the following Swift code: \n\nstruct s1Struct {\n var abc = "Hello"\n \n func change() {\n abc = "bye"\n }\n}\n\nvar a = s1Struct()\na.change()\nprint(a.abc)

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