ios - Proper declaration of global C-constants in Objective-C -

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i'm trying declare , initialize global c-variables. 

const int numberoftickmarks = 6; const double tickvalues[numberoftickmarks] = {500, 2000, 3000, 4000, 6000, 8000};

when in header file (before @interface), linker error. when in .m file (before @implementation), things seem work desired.

is latter accepted way declare global constants c/objective-c?

your global variables should declared in header file:

extern const int numberoftickmarks; extern const double tickvalues[numberoftickmarks];

without extern, linker errors inevitable.

in implementation file, have define them again this:

const int numberoftickmarks = 6; const double tickvalues[numberoftickmarks] = {500, 2000, 3000, 4000, 6000, 8000};

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