pr-setting-database

pr-setting-database is a variable defined in `printing.el'.
Its value is

((no-duplex nil nil nil
	    (pr-file-duplex)
	    (pr-file-tumble)))

Documentation:
Specify an alist for settings in general.

The elements have the following form:

(SYMBOL INHERITS LOCAL KILL-LOCAL SETTING...)

Where:

SYMBOL It's a symbol to identify the setting group.

INHERITS Specify the inheritance for SYMBOL group. It's a symbol name
setting from which the current setting inherits the context.
If INHERITS is nil, means that there is no inheritance.
This is a simple inheritance mechanism.

Let's see an example to illustrate the inheritance mechanism:

(setq pr-setting-database
'((no-duplex ; setting symbol name
nil ; inherits
nil nil ; local kill-local
(pr-file-duplex . nil) ; settings
(pr-file-tumble . nil)
)
(no-duplex-and-landscape ; setting symbol name
no-duplex ; inherits
nil nil ; local kill-local
(pr-file-landscape . nil) ; settings
)))

The example above has two setting groups: no-duplex and
no-duplex-and-landscape. When setting no-duplex is activated
through `inherits-from:' (see option `pr-ps-utility',
`pr-mode-alist' and `pr-ps-printer-alist'), the variables
pr-file-duplex and pr-file-tumble are both set to nil.

Now when setting no-duplex-and-landscape is activated through
`inherits-from:', the variable pr-file-landscape is set to nil
and also the settings for no-duplex are done, because
no-duplex-and-landscape inherits settings from no-duplex.

Take care with circular inheritance. It's an error if circular
inheritance happens.

LOCAL Non-nil means that all settings for SYMBOL group will be
declared local buffer.

KILL-LOCAL Non-nil means that all settings for SYMBOL group will be
killed at end. It has effect only when LOCAL is non-nil.

SETTING It's a cons like:

(VARIABLE . VALUE)

Which associates VARIABLE with VALUE. When this entry is
selected, it's executed the following command:

* If LOCAL is non-nil:
(set (make-local-variable VARIABLE) (eval VALUE))

* If LOCAL is nil:
(set VARIABLE (eval VALUE))

Note that VALUE can be any valid lisp expression. So, don't
forget to quote symbols and constant lists.
This setting is ignored if VARIABLE is equal to keyword
`inherits-from:'.
Examples:
'(ps-landscape-mode . nil)
'(ps-spool-duplex . t)
'(pr-gs-device . (my-gs-device t))

You can customize this variable.