Having the prototype available before the first use of the function allows the compiler to check that the correct number and type of arguments are used in the function call and that the returned value, if any, is being used reasonably. The function definition itself can act as an implicit function declaration.
While shellac is not usually the finish paint choice, it is often thought of as the best paint primer available. It has properties that oil and water based paints can't match, and provides a more dependable seal than most other primers are able to provide.
after rolling one coat over the table with a foam sponge roller i knew that i did not need to use shellac since the chalk paint covered the burn mark 100 % i am pretty sure though if i had used old white chalk paint or pure white chalk paint this would not of been the case