3 Sections of a Program

[JackRabbit]

In chapter 3 it states that programs are logically divided into 3 sections:
1. @interface section
2. @implementation section
3. program section

Why do the first two sections begin with an "@" symbol?

Are all Objective-C programs divided this way?

And are the first  two sections found in what is called a "h. file" or "header file"?


JR

[Fred]

JackRabbit,

The @ prefix is just how Objective-C defines the names of the sections.

If all the code was in a single file, you would see that the code would have the three sections listed.  In most cases the code is broken up into multiple files with .h and .m parts.  In this case the separate .h file contains the @interface part.  The matching .m file contains the @implementation part and the main.m file contains the program part.  The #import commands are used to include all the other code files into the main.m file so the compiler sees all the code in a single file providing the three parts described in the book.  This will become clearer as you work through Steve's book.

Hope this helps clarify.

Fred

[JackRabbit]

Thank you Fred. It does.

It is like an eMail address but instead of .com it is a file. Sort of.....

JR