Which cargo command checks a program for error without creating a binary executable?

The term box and related phrases such as boxing a value are often used when relating to memory layout. What does box refer to?

Using the ? operator at the end of an expression is equivalent to _.

Which is valid syntax for defining an array of i32 values?

The smart pointers Rc and Arc provide reference counting. What is the API for incrementing a reference count?

What happens when an error occurs that is being handled by the question mark (?) operator?

Which cargo command checks a program for error without creating a binary executable?

_ cannot be destructured.