| Allegro CL version 8.2 Unrevised from 8.1 to 8.2. 8.1 version |
Arguments: spec
This function returns true if spec is a suitable
function name (whether or not it actually names an operator) and
returns nil
otherwise. function-name-p thus returns true when
spec is a symbol and when
spec is a list of the form (setf
symbol
)
. According to the ANS, symbols and lists of
that type are the only valid function names.
Allegro CL, however, permits additional lists, defined with def-function-spec-handler, to name
functions. If spec is a proper (Allegro CL) function spec, that is one
whose fspec-first is a
proper function spec name (one defined by def-function-spec-handler) and for which a
:validate
call returns true, function-name-p returns true.
function-name-p has been
added because the behavior of the Common Lisp function fboundp has been brought into
conformance (with the exception noted). In earlier releases of Allegro
CL, fboundp would
return nil
when given an argument which was
not a valid function name. Thus, for example, (fboundp
2)
returned nil
. However, the ANS
requires that fboundp
signal an error if passed an argument which is not a valid function
name, and return nil
only for valid function
names which do not, in fact, name an operator. This function allows
you to modify potentially improper calls to fboundp to avoid errors in 7.0 which
would not have been signaled in earlier releases. A call to fboundp can be modified as
follows:
(if (function-name-p spec) (fboundp spec)) ;; will behave in Allegro CL 7.0 just as (fboundp spec) ;; did in earlier releases.
The ANS seems to forbid function names other than symbols and lists of
the form (setf
symbol
)
. Allegro CL allows
additional lists, specified by def-function-spec-handler. fboundp does not signal an error when
passed a valid Allegro CL function spec, even if it is not an ANS
function spec (and thus fboundp is arguably non-conformant).
Copyright (c) 1998-2016, Franz Inc. Oakland, CA., USA. All rights reserved.
This page was not revised from the 8.1 page.
Created 2010.1.21.
| Allegro CL version 8.2 Unrevised from 8.1 to 8.2. 8.1 version |