c++ - Subscripting a reference to const -


i'm here looking @ c++ code , not understanding something. irrelevant comes yarp (robot middleware) tutorial goes documentation.

virtual void getheader(const bytes& header)  {   const char *target = "humanity";   (int i=0; i<8 && i<header.length(); i++)    {     header.get()[i] = target[i];    } }

now, header reference const , cannot modified within function. get called on it, prototype char *get() const;. how can header.get() subscripted , modified ? program compiles fine. may have not understood happens here i'm basing myself on i've read in c++ primer...

i appreciate little clarification!

have nice day,

char *get() const;

the right hand const means "this member doesn't alter in class that's not mutable", , it's honoring - isn't changing anything. implementation this:

char *bytes::get() const {     return const_cast<char *>(m_bytes); }

the pointer being returned, however, simple "char*". think of way:

(header.get())[i] = target[i]; // or char* p = header.get(); p[i] = target[i];

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