The standard correctly defines the return type of an assignment operator. Actually, the assignment operation itself doesn’t depend on the return value – that’s why the return type isn’t straightforward to understanding. The return type is important for chaining operations. Consider the following construction: a = b = c;. This should be equal to a … Read more
One of the standard conversions, in both C and C++, is the function-to-pointer conversion; when a function name appears in an expression, it can be converted into a pointer to that function. So: foo is equivalent to &foo *foo is equivalent to *(&foo), or foo **foo is eqivalent to **(&foo), or *foo, or foo and … Read more
The standard correctly defines the return type of an assignment operator. Actually, the assignment operation itself doesn’t depend on the return value – that’s why the return type isn’t straightforward to understanding. The return type is important for chaining operations. Consider the following construction: a = b = c;. This should be equal to a … Read more
Here’s a utility function based on a (now-deleted) comment made by “Tiran” in a weblog discussion @Hophat Abc references in his own answer that will work in both Python 2 and 3. Disclaimer: If you read the the linked discussion, you’ll find that some folks think this is so unsafe that it should never be … Read more
* and & as type modifiers int i declares an int. int* p declares a pointer to an int. int& r = i declares a reference to an int, and initializes it to refer to i. C++ only. Note that references must be assigned at initialization, therefore int& r; is not possible. Similarly: void foo(int … Read more
Rust usually focuses on object value (i.e. the interesting part of the contents) rather than object identity (memory addresses). The implementation of Display for &T where T implements Display defers directly to the contents. Expanding that macro manually for the String implementation of Display: impl<‘a> Display for &’a String { fn fmt(&self, f: &mut Formatter) … Read more
Reviewing the basic terminology It’s usually good enough – unless you’re programming assembly – to envisage a pointer containing a numeric memory address, with 1 referring to the second byte in the process’s memory, 2 the third, 3 the fourth and so on…. What happened to 0 and the first byte? Well, we’ll get to … Read more
You haven’t defined struct stasher_file by your first definition. What you have defined is an nameless struct type and a variable stasher_file of that type. Since there’s no definition for such type as struct stasher_file in your code, the compiler complains about incomplete type. In order to define struct stasher_file, you should have done it … Read more
Take it this way: int *i means the value to which i points is an integer. char **p means that p is a pointer which is itself a pointer to a char.
In this case the value at the pointer is copied (though this is not necessarily the case as the optimiser may optimise it out). int val = *pPtr; In this case however no copy will take place: int& rVal = *pPtr; The reason no copy takes place is because a reference is not a machine … Read more