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3.9.3 Package Essentials
A package begins with
    Package $PackageName
and ends with
PackageName is a string that will be used to identify the package. The dollar sign is required. There are no restrictions on the string PackageName, but keep in mind that it serves to distinguish functions in the package from those in all other CoCoA packages. A name of the form contrib/subject is typical.

In between the Package declaration and its EndPackage one may: (1) declare Aliases (see below), (2) define functions, and (3) make comments (please).

If a function F in the package appears in the definition of another function within the package, it must be referred to as $.F (or $PackageName.F, or using a local alias, see below).

Typically, the user will read in the package using the Source command. After that, to save on typing, the user will choose a global alias with which to refer to the package using the syntax:
    Alias ShortName := $PackageName;
where ShortName is any convenient string, hopefully not conflicting with other global aliases. (A list of the global aliases is returned by the function Aliases .)

A package function, F, is then called using the name ShortName.F.