When one definition form simply macroexpands into another, or otherwise has an identical effect as far as the dspec system is concerned, the dspec system should consider them variant forms of the same class.
to convert one definer to the other during canonicalization. A pre-defined example of this in LispWorks is
. These cannot be distinguished (other than in the source code), so
has been defined as a dspec alias for
are distinct subclasses of
, since we can easily tell which type of definition is in effect.
As an explicit example, suppose you have a defining macro
(defmacro parameterdef (value name)
`(defparameter ,name ,value))
(dspec:define-dspec-alias parameterdef (value name)
would be a suitable appropriate alias definition. This
form defines the dspec.
is basically like
for dspecs, so it could be used to describe even complicated conversions, as long as it can be done purely statically and totally in terms of existing dspecs. However, nothing more complicated than
has been found necessary.