ios - What is the difference between 2 strings initilization in swift given below -


string 1:

var string1=string()

string 2:

var edittag: string!

the top 1 declares , creates instance of string.

the bottom declares implicitly-unwrapped optional variable can hold string doesn't create instance of string.

because bottom optional has value of nil until contains instance of class. implicitly unwrapping ! make promise filled instance, in init function or similar. because of there's no need check if it's filled or unwrap before using it.


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