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In the for-as-package subclause the for or as construct iterates over the symbols in a package. In this syntax, a compound preposition is used to designate access to a package. The variable var takes on the value of each symbol in the supplied package. The following loop keywords serve as valid prepositions within this syntax:
The keyword being introduces either the Loop schema symbol, present-symbol, or external-symbol.
The loop keyword each follows the loop keyword being when symbol, present-symbol, or external-symbol is used. The loop keyword the is used with symbols, present-symbols, and external-symbols only for ease of reading. This agreement isn’t required.
These Loop schemas iterate over the symbols
that are present in a package.
The package to be iterated over is supplied in the same way that package arguments to find-package are supplied. If the package for the iteration is not supplied, the current package is used. If a package that does not exist is supplied, an error of type package-error is signaled.
These Loop schemas iterate over symbols that are accessible in a given package. The package to be iterated over is supplied in the same way that package arguments to find-package are supplied. If the package for the iteration is not supplied, the current package is used. If a package that does not exist is supplied, an error of type package-error is signaled.
These Loop schemas iterate over the external symbols of a package. The package to be iterated over is supplied in the same way that package arguments to find-package are supplied. If the package for the iteration is not supplied, the current package is used. If a package that does not exist is supplied, an error of type package-error is signaled.
These loop prepositions introduce package.
In effect
being {each | the} {symbol | symbols | present-symbol | present-symbols | external-symbol | external-symbols} {in | of}
is a compound preposition.
Iteration stops when there are no more symbols to be referenced in the supplied package.