define - constant or literal Objective-C -

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we have following code (in .h. or .m file of objective-c app)

#define square_size 28 #define app_delegate [[uiapplication sharedapplication] appdelegate]

are both of them constants or literals ?

what proper name? , literals suspect, why call them constants :)?

they're neither, they're macros.

a constant this:

const int square_size = 28;

the difference between macro , constant here constant has type while macro text fragment gets inserted @ place it's mentioned before compiler parsing source code.

and literal 28 or @"this string", value.


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