資料來源 : pyDict

復引用

資料來源 : Free On-Line Dictionary of Computing

dereference
     
         To access the thing to which a pointer points,
        i.e. to follow the pointer.  E.g. in {C}, the declarations
     
        	int i;
        	int *p = &i;
     
        declare i as an integer and p as a pointer to integer.  p is
        initialised to point at i ("&i" is the address of i - the
        inverse of "*").  The expression *p dereferences p to yield i
        as an {lvalue}, i.e. something which can appear either on the
        left of an {assignment} or anywhere an integer expression is
        valid.  Thus
     
        	*p = 17;
     
        would set i to 17.  *p++ is not the same as i++ however since
        it is parsed as *(p++), i.e. increment p (which would be an
        invalid thing to do if it was pointing to a single int, as in
        this example) then dereference p's old value.
     
        The {C} operator "->" also dereferences its left hand argument
        which is assumed to point to a {structure} or {union} of which
        the right hand argument is a {member}.
     
        At first sight the word "dereference" might be thought to mean
        "to cause to stop referring" but its meaning is well
        established in jargon.
     
        (1998-12-15)