You can find the latest version of this manual at
@url{http://common-lisp.net/project/asdf/asdf.html}.
-ASDF Copyright @copyright{} 2001-2011 Daniel Barlow and contributors.
+ASDF Copyright @copyright{} 2001-2012 Daniel Barlow and contributors.
-This manual Copyright @copyright{} 2001-2011 Daniel Barlow and contributors.
+This manual Copyright @copyright{} 2001-2012 Daniel Barlow and contributors.
-This manual revised @copyright{} 2009-2011 Robert P. Goldman and Francois-Rene Rideau.
+This manual revised @copyright{} 2009-2012 Robert P. Goldman and Francois-Rene Rideau.
Permission is hereby granted, free of charge, to any person obtaining
a copy of this software and associated documentation files (the
@emph{Nota Bene}:
We have released ASDF 2.000 on May 31st 2010.
Subsequent releases of ASDF 2 have since then been included
-in all actively maintained CL implementations that bundle ASDF,
-and made to work with all actively used CL implementations and a few more.
+in all actively maintained CL implementations that used to bundle ASDF 1,
+plus some implementations that didn't use to,
+and has been made to work with all actively used CL implementations and a few more.
@xref{FAQ,,``What has changed between ASDF 1 and ASDF 2?''}.
Furthermore, it is possible to upgrade from ASDF 1 to ASDF 2 on the fly.
For this reason, we have stopped supporting ASDF 1;
if you are using ASDF 1 and are experiencing any kind of issues or limitations,
we recommend you upgrade to ASDF 2
---- and we explain how to do it. @xref{Loading ASDF}.
+--- and we explain how to do that. @xref{Loading ASDF}.
+
+Also note that ASDF is not to be confused with ASDF-Install.
+ASDF-Install is not part of ASDF, but a separate piece of software.
+ASDF-Install is also unmaintained and obsolete.
+We recommend you use Quicklisp instead,
+which works great and is being actively maintained.
+If you want to download software from version control instead of tarballs,
+so you may more easily modify it, we recommend clbuild.
@node Loading ASDF, Configuring ASDF, Introduction, Top
@vindex *central-registry*
@cindex link farm
@findex load-system
+@findex require-system
@findex compile-system
@findex test-system
@cindex system directory designator
You can usually load this copy using Common Lisp's @code{require} function:
@lisp
-(require :asdf)
+(require "asdf")
@end lisp
As of the writing of this manual,
the following implementations provide ASDF 2 this way:
-abcl allegro ccl clisp cmucl ecl sbcl xcl.
-The following implementations don't provide it yet but might in a future release:
-lispworks scl.
-The following implementations are obsolete and most probably will never bundle it:
+abcl allegro ccl clisp cmucl ecl lispworks sbcl xcl.
+The following implementation doesn't provide it yet but will in a future release:
+scl.
+The following implementations are obsolete, not actively maintained,
+and most probably will never bundle it:
cormancl gcl genera mcl.
If the implementation you are using doesn't provide ASDF 2,
you may also send a bug report to your Lisp vendor and complain
about their failing to provide ASDF.
+NB: all implementations except clisp also accept
+@code{(require "ASDF")}, @code{(require 'asdf)} and @code{(require :asdf)}.
+For portability's sake, you probably want to use @code{(require "asdf")}.
+
@section Checking whether ASDF is loaded
and upgrade with:
@lisp
-(require :asdf)
+(require "asdf")
(asdf:load-system :asdf)
@end lisp
you will require a special configuration step and an old-style loading:
@lisp
-(require :asdf)
+(require "asdf")
(push #p"@var{/path/to/new/asdf/}" asdf:*central-registry*)
(asdf:oos 'asdf:load-op :asdf)
@end lisp
If you install software there, you don't need further configuration.
If you're installing software yourself at a location that isn't standard,
you have to tell ASDF where you installed it. See below.
-If you're using some tool to install software,
+If you're using some tool to install software (e.g. Quicklisp),
the authors of that tool should already have configured ASDF.
The simplest way to add a path to your search path,
say @file{/home/luser/.asd-link-farm/}
is to create the directory
@file{~/.config/common-lisp/source-registry.conf.d/}
-and there create a file with any name of your choice but the type @file{conf},
+and there create a file with any name of your choice,
+and with the type @file{conf},
for instance @file{42-asd-link-farm.conf}
containing the line:
and the machine you resume it at the time you resume it.
-@section Configuring ASDF to find your systems -- old style
+@section Configuring ASDF to find your systems --- old style
The old way to configure ASDF to find your systems is by
@code{push}ing directory pathnames onto the variable
For instance, if you wanted ASDF to find the @file{.asd} file
@file{/home/me/src/foo/foo.asd} your initialization script
-could after it loads ASDF with @code{(require :asdf)}
+could after it loads ASDF with @code{(require "asdf")}
configure it with:
@lisp
to the @code{asdf:*central-registry*}.
ASDF knows how to follow such @emph{symlinks}
to the actual file location when resolving the paths of system components
-(on Windows, you can use Windows shortcuts instead of POSIX symlinks).
+(on Windows, you can use Windows shortcuts instead of POSIX symlinks;
+if you try aliases under MacOS, we are curious to hear about your experience).
For example, if @code{#p"/home/me/cl/systems/"} (note the trailing slash)
is a member of @code{*central-registry*}, you could set up the
@section Configuring where ASDF stores object files
-@findex clear-output-locations
+@findex clear-output-translations
ASDF lets you configure where object files will be stored.
Sensible defaults are provided and
@node Using ASDF, Defining systems with defsystem, Configuring ASDF, Top
@comment node-name, next, previous, up
+
+@section Resetting Configuration
+
+When you dump and restore an image, or when you tweak your configuration,
+you may want to reset the ASDF configuration.
+For that you may use the following function:
+
+@defun clear-configuration
+ undoes any ASDF configuration,
+ regarding source-registry or output-translations.
+@end defun
+
+If you use SBCL, CMUCL or SCL, you may use this snippet
+so that the ASDF configuration be cleared automatically as you dump an image:
+
+@example
+#+(or cmu sbcl scl)
+(pushnew 'clear-configuration
+ #+(or cmu scl) ext:*before-save-initializations*
+ #+sbcl sb-ext:*save-hooks*)
+@end example
+
+For compatibility with all Lisp implementations, however,
+you might want instead your build script to explicitly call
+@code{(asdf:clear-configuration)} at an appropriate moment before dumping.
+
+
@chapter Using ASDF
@section Loading a system
ASDF provides three commands for the most common system operations:
@code{load-system}, @code{compile-system} or @code{test-system}.
+It also provides @code{require-system}, a version of @code{load-system}
+that skips trying to update systems that are already loaded.
Because ASDF is an extensible system
for defining @emph{operations} on @emph{components},
@itemize
@item
Load ASDF itself into your Lisp image, either through
-@code{(require :asdf)} or else through
+@code{(require "asdf")} or else through
@code{(load "/path/to/asdf.lisp")}.
@item
system-definition := ( defsystem system-designator @var{system-option}* )
system-option := :defsystem-depends-on system-list
+ | :weakly-depends-on @var{system-list}
+ | :class class-name (see discussion below)
| module-option
| option
the current package @code{my-system-asd} can be specified as
@code{:my-component-type}, or @code{my-component-type}.
+@subsection System class names
+
+A system class name will be looked up in the same way as a Component
+type (see above). Typically, one will not need to specify a system
+class name, unless using a non-standard system class defined in some
+ASDF extension, typically loaded through @code{DEFSYSTEM-DEPENDS-ON},
+see below. For such class names in the ASDF package, we recommend that
+the @code{:class} option be specified using a keyword symbol, such as
+
+@example
+:class :MY-NEW-SYSTEM-SUBCLASS
+@end example
+
+This practice will ensure that package name conflicts are avoided.
+Otherwise, the symbol @code{MY-NEW-SYSTEM-SUBCLASS} will be read into
+the current package @emph{before} it has been exported from the ASDF
+extension loaded by @code{:defsystem-depends-on}, causing a name
+conflict in the current package.
+
@subsection Defsystem depends on
+@cindex :defsystem-depends-on
The @code{:defsystem-depends-on} option to @code{defsystem} allows the
programmer to specify another ASDF-defined system or set of systems that
Typically this is used to load an ASDF extension that is used in the
system definition.
+@subsection Weakly depends on
+@cindex :weakly-depends-on
+
+The @code{:weakly-depends-on} option to @code{defsystem} allows the
+programmer to specify another ASDF-defined system or set of systems that
+ASDF should @emph{try} to load, but need not load in order to be
+successful. Typically this is used if there are a number of systems
+that, if present, could provide additional functionality, but which are
+not necessary for basic function.
+
+Currently, although it is specified to be an option only to
+@code{defsystem}, this option is accepted at any component, but it probably
+only makes sense at the @code{defsystem} level. Programmers are cautioned not
+to use this component option except at the @code{defsystem} level, as
+this anomalous behavior may be removed without warning.
+
@subsection Pathname specifiers
@cindex pathname specifiers
Note however, that @code{#p...} is a shorthand for @code{#.(parse-namestring ...)}
and that the behavior of @code{parse-namestring} is completely non-portable,
unless you are using Common Lisp @code{logical-pathname}s
-(@pxref{The defsystem grammar,,Warning about logical pathnames}, below).
+(@pxref{The defsystem grammar,,Using logical pathnames}, below).
Pathnames made with @code{#.(make-pathname ...)}
can usually be done more easily with the string syntax above.
The only case that you really need a pathname object is to override
@xref{Common attributes of components}.
-@subsection Warning about logical pathnames
+@subsection Using logical pathnames
@cindex logical pathnames
-We recommend that you not use logical pathnames
-in your asdf system definitions at this point,
-but logical pathnames @emph{are} supported.
+We do not generally recommend the use of logical pathnames,
+especially not so to newcomers to Common Lisp.
+However, we do support the use of logical pathnames by old timers,
+when such is their preference.
To use logical pathnames,
you will have to provide a pathname object as a @code{:pathname} specifier
to components that use it, using such syntax as
@code{#p"LOGICAL-HOST:absolute;path;to;component.lisp"}.
-You only have to specify such logical pathname for your system or
-some top-level component. Sub-components' relative pathnames, specified
-using the string syntax
-for names, will be properly merged with the pathnames of their parents.
+You only have to specify such logical pathname
+for your system or some top-level component.
+Sub-components' relative pathnames,
+specified using the string syntax for names,
+will be properly merged with the pathnames of their parents.
The specification of a logical pathname host however is @emph{not}
otherwise directly supported in the ASDF syntax
for pathname specifiers as strings.
The @code{asdf-output-translation} layer will
-avoid trying to resolve and translate logical-pathnames.
-The advantage of this is that you can define yourself what translations you want to use
+avoid trying to resolve and translate logical pathnames.
+The advantage of this is that
+you can define yourself what translations you want to use
with the logical pathname facility.
-The disadvantage is that if you do not define such translations, any
-system that uses logical pathnames will behave differently under
+The disadvantage is that if you do not define such translations,
+any system that uses logical pathnames will behave differently under
asdf-output-translations than other systems you use.
If you wish to use logical pathnames you will have to configure the
ASDF currently provides no specific support
for defining logical pathname translations.
+Note that the reasons we do not recommend logical pathnames are that
+(1) there is no portable way to set up logical pathnames before they are used,
+(2) logical pathnames are limited to only portably use
+a single character case, digits and hyphens.
+While you can solve the first issue on your own,
+describing how to do it on each of fifteen implementations supported by ASDF
+is more than we can document.
+As for the second issue, mind that the limitation is notably enforced on SBCL,
+and that you therefore can't portably violate the limitations
+but must instead define some encoding of your own and add individual mappings
+to name physical pathnames that do not fit the restrictions.
+This can notably be a problem when your Lisp files are part of a larger project
+in which it is common to name files or directories in a way that
+includes the version numbers of supported protocols,
+or in which files are shared with software written
+in different programming languages where conventions include the use of
+underscores, dots or CamelCase in pathnames.
+
@subsection Serial dependencies
@cindex serial dependencies
@menu
* Operations::
* Components::
+* Functions::
@end menu
@node Operations, Components, The object model of ASDF, The object model of ASDF
Operations that print output should send that output to the standard
CL stream @code{*standard-output*}, as the Lisp compiler and loader do.
-@node Components, , Operations, The object model of ASDF
+@node Components, Functions, Operations, The object model of ASDF
@comment node-name, next, previous, up
@section Components
@cindex component
@verbatim
(this-op {(other-op required-components)}+)
-required-components := component-name
+simple-component-name := string
+ | symbol
+
+required-components := simple-component-name
| (required-components required-components)
-component-name := string
- | (:version string minimum-version-object)
+component-name := simple-component-name
+ | (:version simple-component-name minimum-version-object)
@end verbatim
Side note:
)
@end lisp
+@node Functions, , Components, The object model of ASDF
+@comment node-name, next, previous, up
+@section Functions
+@findex version-satisfies
+
+@deffn version-satisfies @var{version} @var{version-spec}
+Does @var{version} satisfy the @var{version-spec}. A generic function.
+ASDF provides built-in methods for @var{version} being a
+@code{component} or @code{string}. @var{version-spec} should be a
+string.
+
+In the wild, we typically see version numbering only on components of
+type @code{system}.
+
+For more information about how @code{version-satisfies} interprets
+version strings and specifications, @pxref{The defsystem grammar} and
+@ref{Common attributes of components}.
+@end deffn
+
@node Controlling where ASDF searches for systems, Controlling where ASDF saves compiled files, The object model of ASDF, Top
@comment node-name, next, previous, up
@chapter Controlling where ASDF searches for systems
@code{asdf:*central-registry*}
before it searches in the source registry above.
-@xref{Configuring ASDF,,Configuring ASDF to find your systems -- old style}.
+@xref{Configuring ASDF,,Configuring ASDF to find your systems --- old style}.
By default, @code{asdf:*central-registry*} will be empty.
(:tree DIRECTORY-PATHNAME-DESIGNATOR) |
;; override the defaults for exclusion patterns
- (:exclude PATTERN ...) |
+ (:exclude EXCLUSION-PATTERN ...) |
;; augment the defaults for exclusion patterns
- (:also-exclude PATTERN ...) |
+ (:also-exclude EXCLUSION-PATTERN ...) |
;; Note that the scope of a an exclude pattern specification is
;; the rest of the current configuration expression or file.
DIRECTORY-PATHNAME-DESIGNATOR := PATHNAME-DESIGNATOR ;; interpreted as a directory name
PATHNAME-DESIGNATOR :=
- NULL | ;; Special: skip this entry.
- ABSOLUTE-COMPONENT-DESIGNATOR |
- (ABSOLUTE-COMPONENT-DESIGNATOR RELATIVE-COMPONENT-DESIGNATOR ...)
+ NIL | ;; Special: skip this entry.
+ ABSOLUTE-COMPONENT-DESIGNATOR ;; see pathname DSL
+
+EXCLUSION-PATTERN := a string without wildcards, that will be matched exactly
+ against the name of a any subdirectory in the directory component
+ of a path. e.g. @code{"_darcs"} will match @file{#p"/foo/bar/_darcs/src/bar.asd"}
+@end example
+Pathnames are designated using another DSL,
+shared with the output-translations configuration DSL below.
+The DSL is resolved by the function @code{asdf::resolve-location},
+to be documented and exported at some point in the future.
+
+@example
ABSOLUTE-COMPONENT-DESIGNATOR :=
- STRING | ;; namestring (better be absolute or bust, directory assumed where applicable)
+ (ABSOLUTE-COMPONENT-DESIGNATOR RELATIVE-COMPONENT-DESIGNATOR ...) |
+ STRING | ;; namestring (better be absolute or bust, directory assumed where applicable).
+ ;; In output-translations, directory is assumed and **/*.*.* added if it's last.
+ ;; On MCL, a MacOSX-style POSIX namestring (for MacOS9 style, use #p"...");
+ ;; Note that none of the above applies to strings used in *central-registry*,
+ ;; which doesn't use this DSL: they are processed as normal namestrings.
+ ;; however, you can compute what you put in the *central-registry*
+ ;; based on the results of say (asdf::resolve-location "/Users/fare/cl/cl-foo/")
PATHNAME | ;; pathname (better be an absolute path, or bust)
+ ;; In output-translations, unless followed by relative components,
+ ;; it better have appropriate wildcards, as in **/*.*.*
:HOME | ;; designates the user-homedir-pathname ~/
:USER-CACHE | ;; designates the default location for the user cache
- :SYSTEM-CACHE | ;; designates the default location for the system cache
- :HERE ;; designates the location of the configuration file
- ;; (or *default-pathname-defaults*, if invoked interactively)
+ :HERE | ;; designates the location of the configuration file
+ ;; (or *default-pathname-defaults*, if invoked interactively)
+ :ROOT ;; magic, for output-translations source only: paths that are relative
+ ;; to the root of the source host and device
+ ;; Not valid anymore: :SYSTEM-CACHE (was a security hazard)
RELATIVE-COMPONENT-DESIGNATOR :=
- STRING | ;; namestring (directory assumed where applicable)
- PATHNAME | ;; pathname
- :IMPLEMENTATION | ;; a directory based on implementation, e.g. sbcl-1.0.45-linux-amd64
+ (RELATIVE-COMPONENT-DESIGNATOR RELATIVE-COMPONENT-DESIGNATOR ...) |
+ STRING | ;; relative directory pathname as interpreted by coerce-pathname.
+ ;; In output translations, if last component, **/*.*.* is added
+ PATHNAME | ;; pathname; unless last component, directory is assumed.
+ :IMPLEMENTATION | ;; directory based on implementation, e.g. sbcl-1.0.45-linux-x64
:IMPLEMENTATION-TYPE | ;; a directory based on lisp-implementation-type only, e.g. sbcl
- :UID | ;; current UID -- not available on Windows
- :USER ;; current USER name -- NOT IMPLEMENTED(!)
-
-PATTERN := a string without wildcards, that will be matched exactly
- against the name of a any subdirectory in the directory component
- of a path. e.g. @code{"_darcs"} will match @file{#p"/foo/bar/_darcs/src/bar.asd"}
+ :DEFAULT-DIRECTORY | ;; a relativized version of the default directory
+ :*/ | ;; any direct subdirectory (since ASDF 2.011.4)
+ :**/ | ;; any recursively inferior subdirectory (since ASDF 2.011.4)
+ :*.*.* | ;; any file (since ASDF 2.011.4)
+ ;; Not supported (anymore): :UID and :USERNAME
@end example
For instance, as a simple case, my @file{~/.config/common-lisp/source-registry.conf},
-which is the default place ASDF looks for this configuration,
-once contained:
+which is the default place ASDF looks for this configuration, once contained:
@example
(:source-registry
(:tree (:home "cl")) ;; will expand to e.g. "/home/joeluser/cl/"
(DIRECTORY-DESIGNATOR (:function TRANSLATION-FUNCTION))
DIRECTORY-DESIGNATOR :=
+ NIL | ;; As source: skip this entry. As destination: same as source
T | ;; as source matches anything, as destination leaves pathname unmapped.
- ABSOLUTE-COMPONENT-DESIGNATOR |
- (ABSOLUTE-COMPONENT-DESIGNATOR RELATIVE-COMPONENT-DESIGNATOR ...)
-
-ABSOLUTE-COMPONENT-DESIGNATOR :=
- NULL | ;; As source: skip this entry. As destination: same as source
- :ROOT | ;; magic: paths that are relative to the root of the source host and device
- STRING | ;; namestring (directory is assumed, better be absolute or bust, ``/**/*.*'' added)
- PATHNAME | ;; pathname (better be an absolute directory or bust)
- :HOME | ;; designates the user-homedir-pathname ~/
- :USER-CACHE | ;; designates the default location for the user cache
- :SYSTEM-CACHE ;; designates the default location for the system cache
-
-RELATIVE-COMPONENT-DESIGNATOR :=
- STRING | ;; namestring, directory is assumed. If the last component, /**/*.* is added
- PATHNAME | ;; pathname; unless last component, directory is assumed.
- :IMPLEMENTATION | ;; a directory based on implementation, e.g. sbcl-1.0.45-linux-amd64
- :IMPLEMENTATION-TYPE | ;; a directory based on lisp-implementation-type only, e.g. sbcl
- :*/ | ;; any direct subdirectory (since ASDF 2.011.4)
- :**/ | ;; any recursively inferior subdirectory (since ASDF 2.011.4)
- :*.*.* | ;; any file (since ASDF 2.011.4)
- :UID | ;; current UID -- not available on Windows
- :USER ;; current USER name -- NOT IMPLEMENTED(!)
+ ABSOLUTE-COMPONENT-DESIGNATOR ;; same as in the source-registry language
TRANSLATION-FUNCTION :=
SYMBOL | ;; symbol of a function that takes two arguments,
@comment node-name, next, previous, up
@chapter Miscellaneous additional functionality
-@emph{FIXME: Add discussion of @code{run-shell-command}? Others?}
-
ASDF includes several additional features that are generally
-useful for system definition and development. These include:
+useful for system definition and development.
+
+@section Controlling file compilation
+
+When declaring a component (system, module, file),
+you can specify a keyword argument @code{:around-compile function}.
+If left unspecified,
+the value will be inherited from the parent component if any,
+or with a default of @code{nil}
+if no value is specified in any transitive parent.
+
+The argument must be a either @code{nil}, a fbound symbol,
+a lambda-expression (e.g. @code{(lambda (thunk) ...(funcall thunk) ...)})
+a function object (e.g. using @code{#.#'} but that's discouraged
+because it prevents the introspection done by e.g. asdf-dependency-grovel),
+or a string that when read yields a symbol or a lambda-expression.
+@code{nil} means the normal compile-file function will be called.
+A non-nil value designates a function of one argument
+that will be called with a thunk for calling
+the compile-file function with proper arguments.
+
+Note that by using a string, you may reference
+a function, symbol and/or package
+that will only be created later during the build, but
+isn't yet present at the time the defsystem form is evaluated.
+However, if your entire system is using such a hook, you may have to
+explicitly override the hook with @code{nil} for all the modules and files
+that are compiled before the hook is defined.
+
+Using this hook, you may achieve such effects as:
+locally renaming packages,
+binding @var{*readtables*} and other syntax-controlling variables,
+handling warnings and other conditions,
+proclaiming consistent optimization settings,
+saving code coverage information,
+maintaining meta-data about compilation timings,
+setting gensym counters and PRNG seeds and other sources of non-determinism,
+overriding the source-location and/or timestamping systems,
+checking that some compile-time side-effects were properly balanced,
+etc.
+
+Note that there is no around-load hook. This is on purpose.
+Some implementations such as ECL or GCL link object files,
+which allows for no such hook.
+Other implementations allow for concatenating FASL files,
+which doesn't allow for such a hook either.
+We aim to discourage something that's not portable,
+and has some dubious impact on performance and semantics
+even when it is possible.
+Things you might want to do with an around-load hook
+are better done around-compile,
+though it may at times require some creativity
+(see e.g. the @code{package-renaming} system).
+
+
+@section Controlling source file character encoding
+
+Starting with ASDF 2.21, components accept a @code{:encoding} option.
+By default, only @code{:default}, @code{:utf-8}
+and @code{:autodetect} are accepted.
+@code{:autodetect} is the default, and calls
+@code{*encoding-detection-hook*} which by default always returns
+@code{*default-encoding*} which itself defaults to @code{:default}.
+In other words, there now are plenty of extension hooks, but
+by default ASDF follows the backwards compatible behavior
+of using whichever @code{:default} encoding your implementation uses,
+which itself may or may not vary based on environment variables
+and other locale settings.
+In practice this means that only source code that only uses ASCII
+is guaranteed to be read the same on all implementations
+independently from any user setting.
+
+Additionally, for backward-compatibility with older versions of ASDF
+and/or with implementations that do not support unicode and its many encodings,
+you may want to use
+the reader conditionals @code{#+asdf-unicode #+asdf-unicode}
+to protect any @code{:encoding @emph{encoding}} statement
+as @code{:asdf-unicode} will be present in @code{*features*}
+only if you're using a recent ASDF
+on an implementation that supports unicode.
+We recommend that you avoid using unprotected @code{:encoding} specifications
+until after ASDF 2.21 becomes widespread, hopefully by the end of 2012.
+
+While it offers plenty of hooks for extension,
+and one such extension is being developed (see below),
+ASDF itself only recognizes one encoding beside @code{:default},
+and that is @code{:utf-8}, which is the @emph{de facto} standard,
+already used by the vast majority of libraries that use more than ASCII.
+On implementations that do not support unicode,
+the feature @code{:asdf-unicode} is absent, and
+the @code{:default} external-format is used
+to read even source files declared as @code{:utf-8}.
+On these implementations, non-ASCII characters
+intended to be read as one CL character
+may thus end up being read as multiple CL characters.
+In most cases, this shouldn't affect the software's semantics:
+comments will be skipped just the same, strings with be read and printed
+with slightly different lengths, symbol names will be accordingly longer,
+but none of it should matter.
+But a few systems that actually depend on unicode characters
+may fail to work properly, or may work in a subtly different way.
+See for instance @code{lambda-reader}.
+
+We invite you to embrace UTF-8
+as the encoding for non-ASCII characters starting today,
+even without any explicit specification in your @code{.asd} files.
+Indeed, on some implementations and configurations,
+UTF-8 is already the @code{:default},
+and loading your code may cause errors if it is encoded in anything but UTF-8.
+Therefore, even with the legacy behavior,
+non-UTF-8 is guaranteed to break for some users,
+whereas UTF-8 is pretty much guaranteed not to break anywhere
+(provided you do @emph{not} use a BOM),
+although it might be read incorrectly on some implementations.
+In the future, we intend to make @code{:utf-8}
+the default value of @code{*default-encoding*},
+to be enforced everywhere, so at least the code is guaranteed
+to be read correctly everywhere it can be.
+
+If you need non-standard character encodings for your source code,
+use the extension system @code{asdf-encodings}, by specifying
+@code{:defsystem-depends-on (:asdf-encodings)} in your @code{defsystem}.
+This extension system will register support for more encodings using the
+@code{*encoding-external-format-hook*} facility,
+so you can explicitly specify @code{:encoding :latin1}
+in your @code{.asd} file.
+Using the @code{*encoding-detection-hook*} it will also
+eventually implement some autodetection of a file's encoding
+from an emacs-style @code{-*- mode: lisp ; coding: latin1 -*-} declaration,
+or otherwise based on an analysis of octet patterns in the file.
+At this point, asdf-encoding only supports the encodings
+that are supported as part of your implementation.
+Since the list varies depending on implementations,
+we once again recommend you use @code{:utf-8} everywhere,
+which is the most portable (next is @code{:latin1}).
+
+If you're not using a version of Quicklisp that has it,
+you may get the source for @code{asdf-encodings} using git:
+@kbd{git clone git://common-lisp.net/projects/asdf/asdf-encodings.git}
+or
+@kbd{git clone ssh://common-lisp.net/project/asdf/git/asdf-encodings.git}.
+You can also browse the repository on
+@url{http://common-lisp.net/gitweb?p=projects/asdf/asdf-encodings.git}.
+
+In the future, we intend to change the default @code{*default-encoding*}
+to @code{:utf-8}, which is already the de facto standard
+for most libraries that use non-ASCII characters:
+utf-8 works everywhere and was backhandedly enforced by
+a lot of people using SBCL and utf-8 and sending reports to authors
+so they make their packages compatible.
+A survey showed only about a handful few libraries
+are incompatible with non-UTF-8, and then, only in comments,
+and we believe that authors will adopt UTF-8 when prompted.
+See the April 2012 discussion on the asdf-devel mailing-list.
+For backwards compatibility with users who insist on a non-UTF-8 encoding,
+but cannot immediately transition to using @code{asdf-encodings}
+(maybe because it isn't ready), it will still be possible to use
+the @code{:encoding :default} option in your @code{defsystem} form
+to restore the behavior of ASDF 2.20 and earlier.
+This shouldn't be required in libraries,
+because user pressure as mentioned above will already have pushed
+library authors towards using UTF-8;
+but authors of end-user programs might care.
+
+When you use @code{asdf-encodings}, any further loaded @code{.asd} file
+will use the autodetection algorithm to determine its encoding;
+yet if you depend on this detection happening,
+you may want to explicitly load @code{asdf-encodings} early in your build,
+for by the time you can use @code{:defsystem-depends-on},
+it is already too late to load it.
+In practice, this means that the @code{*default-encoding*}
+is usually used for @code{.asd} files.
+Currently, this defaults to @code{:default} for backwards compatibility,
+and that means that you shouldn't rely on non-ASCII characters in a .asd file.
+Since component (path)names are the only real data in these files,
+and non-ASCII characters are not very portable for file names,
+this isn't too much of an issue.
+We still encourage you to use either plain ASCII or UTF-8
+in @code{.asd} files,
+as we intend to make @code{:utf-8} the default encoding in the future.
+This might matter, for instance, in meta-data about author's names.
+
+
+@section Miscellaneous Exported Functions
@defun coerce-pathname name @&key type defaults
look at the beginning of @file{asdf.lisp} to see what it does.
@end defun
+@defun run-shell-command
+
+This function is obsolete and present only for the sake of backwards-compatibility:
+``If it's not backwards, it's not compatible''. We strongly discourage its use.
+Its current behavior is only well-defined on Unix platforms
+(which include MacOS X and cygwin). On Windows, anything goes.
+
+Instead we recommend the use of such a function as
+@code{xcvb-driver:run-program/}
+from the @code{xcvb-driver} system that is distributed with XCVB:
+@url{http://common-lisp.net/project/xcvb}.
+It's only alternative that supports
+as many implementations and operating systems as ASDF does,
+and provides well-defined behavior outside Unix (i.e. on Windows).
+(The only unsupported exception is Genera, since on it
+@code{run-shell-command} doesn't make sense anyway on that platform).
+
+@code{run-shell-command} takes as arguments a @code{format} control-string
+and arguments to be passed to @code{format} after this control-string
+to produce a string.
+This string is a command that will be evaluated with a POSIX shell if possible;
+yet, on Windows, some implementations will use CMD.EXE,
+while others (like SBCL) will make an attempt at invoking a POSIX shell
+(and fail if it is not present).
+@end defun
+
+
@node Getting the latest version, FAQ, Miscellaneous additional functionality, Top
@comment node-name, next, previous, up
@chapter Getting the latest version
With ASDF 2, we provide a new stable set of working features
that everyone can rely on from now on.
Use @code{#+asdf2} to detect presence of ASDF 2,
-@code{(asdf:version-satisfies (asdf:asdf-version) "2.000")}
+@code{(asdf:version-satisfies (asdf:asdf-version) "2.345.67")}
to check the availability of a version no earlier than required.
When an old version of ASDF was loaded,
it was very hard to upgrade ASDF in your current image
without breaking everything.
-Instead you have to exit the Lisp process and
+Instead you had to exit the Lisp process and
somehow arrange to start a new one from a simpler image.
Something that can't be done from within Lisp,
making automation of it difficult,
or shallow @code{:tree} entries.
Or you can fix your implementation to not be quite that slow
when recursing through directories.
+@emph{Update}: performance bug fixed the hard way in 2.010.
@item
On Windows, only LispWorks supports proper default configuration pathnames
based on the Windows registry.
-Other implementations make do with environment variables.
+Other implementations make do with environment variables,
+that you may have to define yourself if you're using an older version of Windows.
Windows support is somewhat less tested than Unix support.
Please help report and fix bugs.
Previously, the pathname for a component was lazily computed when operating on a system,
and you would
@code{(defmethod source-file-type ((component cl-source-file) (system (eql (find-system 'foo))))
- (declare (ignorable component system)) "cl")}.
+ (declare (ignorable component system)) "lis")}.
Now, the pathname for a component is eagerly computed when defining the system,
and instead you will @code{(defclass cl-source-file.lis (cl-source-file) ((type :initform "lis")))}
and use @code{:default-component-class cl-source-file.lis} as argument to @code{defsystem},
@itemize
@item
-If ASDF isn't loaded yet, then @code{(require :asdf)}
+If ASDF isn't loaded yet, then @code{(require "asdf")}
should load the version of ASDF that is bundled with your system.
You may have it load some other version configured by the user,
if you allow such configuration.
"lis")
@end lisp
+@comment FIXME: Add a FAQ about how to use a new system class...
+
@node TODO list, Inspiration, FAQ, Top
@comment node-name, next, previous, up