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 comment syntax is not legal?

In matching patterns, values are ignored with _.

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

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

_ cannot be destructured.

Which choice is not a scalar data type?

Which type cast preserves the mathematical value in all cases?