Semicolon after the method name in Objective-C implementation file
Solution 1:
Yes, it is acceptable syntax to do this.
In fact, I always do this in my implementations, because it then is trivial to copy and paste a method definition from interface to implementation and vice versa without having to remember where you are. It helps that I use aligned brackets on separate lines, as well.
Wil Shipley agrees with me on this:
End the definition lines on your method implementations with a semicolon, so you can copy-n-paste them to or from your header (or the "Private" category at the top of your file) as needed when they change. Semicolons are required in the "interface" section, but don't hurt anything in the "implementation" section.
Solution 2:
Grammatically it is OK to put a semicolon there. It serves no purpose, and it is discouraged to do that. Some compilers give warnings about this extra semicolon.
Solution 3:
Yes it will work and compile with no side effects in XCode. I see it commonly done accidentally when copying the method declaration from the header, though I wouldn't recommend adding them to the end of methods purposefully.
Solution 4:
Yes it will work, but the semi-colon is incorrect, however it won't actually cause any crashes.
Reference link here
"Methods for a class are defined, like C functions, within a pair of braces. Before the braces, they’re declared in the same manner as in the interface file, but without the semicolon."