Novice seeking to explain if ((self = [super init])) {...} double parentheses role

Seeking to explain if ((self = [super init])) {...} double parentheses role, single brackets if (self = [super init]) {...} not?
Because the brackets will be judged as a single assignment? Assignment are true? Or? ? Novice beg answers, thank you
Reply:
Behind such an approach can be, ah, what to say no.

Reply:
No problem. Just to look good, understandable


Reply:
Head, personal hobby format
Reply:
seemingly no difference. . .