Symbols can be displayed either with their package information attached or not. In the LispWorks IDE, symbols are displayed with the package name attached by default.
For example, suppose you have created a package
FOO
which includes a symbol named
bar
and a symbol named
baz
. Suppose further that you created a new package
FOO2
, which used the
FOO
package. This can be done as shown below:
(defpackage foo (:use "COMMON-LISP"))
(defpackage foo2 (:use "FOO" "COMMON-LISP"))
Note that in defining both packages, the
COMMON-LISP
package has also been used. It is good practice to use this package, to ensure that commonly-used symbols are available.
When creating packages which use other packages, exported symbols can be called without having to refer to the package name.
To illustrate this, let us return to our example.
Figure 3.6 Two example packages
We have two packages:
FOO1
and
FOO2
.
FOO1
contains symbols
bar
and
baz
. The symbol
bar
has been exported, whereas the symbol
baz
is not exported.
When the current package is
FOO2
, you can refer to
bar
without using the package name. This is because
FOO2
uses
FOO1
and
bar
is exported. However to refer to
baz
you must still use the
FOO1
package name like this:
foo1::baz
. This is because
baz
is not exported.
Note also that when the current package is other than
FOO1
or
FOO2
, you can refer to
foo1:bar
, but you can only refer to
baz
as
foo1::baz
.
Package names are usually displayed alongside symbols in a list. Having a package entry on every line can be unhelpful, especially if the majority of items listed are from the same package. To hide the package names for the symbols in a given type of tool: