In Elan all elementary objects must be declared. This declaration may occur at any place in the program, provided there is only one such place, and in executing the program the declaration of an object precedes all its applications. Thus there is no necessity to collect all declarations at the head of the program but declarations can appear at the place where they are first needed. A declaration may even occur within the body of a loop.
A declaration is a unit which introduces an elementary object with four attributes:
A declaration makes the name of the object known throughout the whole Elan program.