You can find the latest version of this manual at

 https://common-lisp.net/project/asdf/asdf.html.

 Permission is hereby granted, free of charge, to any person obtaining

 a copy of this software and associated documentation files (the

       <li><a name="toc-Pathname-specifiers" href="#Pathname-specifiers">6.3.7 Pathname specifiers</a></li>

       <li><a name="toc-Version-specifiers" href="#Version-specifiers">6.3.8 Version specifiers</a></li>

       <li><a name="toc-Require" href="#Require">6.3.9 Require</a></li>

       <li><a name="toc-feature-requirement" href="#feature-requirement">6.3.15 feature requirement</a></li>

     </ul></li>

     <li><a name="toc-Other-code-in-_002easd-files-1" href="#Other-code-in-_002easd-files">6.4 Other code in .asd files</a></li>

         <li><a name="toc-How-should-my-library-make-a-readtable-available-to-other-systems_003f" href="#How-should-my-library-make-a-readtable-available-to-other-systems_003f">13.6.7.2 How should my library make a readtable available to other systems?</a></li>

       </ul></li>

       <li><a name="toc-How-can-I-capture-ASDF_0027s-output_003f-1" href="#How-can-I-capture-ASDF_0027s-output_003f">13.6.8 How can I capture ASDF&rsquo;s output?</a></li>

     </ul></li>

     <li><a name="toc-ASDF-development-FAQs-1" href="#ASDF-development-FAQs">13.7 ASDF development FAQs</a>

     <ul class="no-bullet">

 <a name="Top"></a>

 <a name="ASDF_003a-Another-System-Definition-Facility"></a>

 <h1 class="top">ASDF: Another System Definition Facility</h1>

 </p>

 <p>This manual describes ASDF, a system definition facility

 <p>You can find the latest version of this manual at

 <a href="https://common-lisp.net/project/asdf/asdf.html">https://common-lisp.net/project/asdf/asdf.html</a>.

 </p>

 </p>

 </p>

 </p>

 <p>Permission is hereby granted, free of charge, to any person obtaining

 a copy of this software and associated documentation files (the

 <p>The old way to configure ASDF to find your systems is by

 <code>push</code>ing directory pathnames onto the variable

 <code>asdf:*central-registry*</code>.

 </p>

 <p>For example, let&rsquo;s say you want ASDF to find the <samp>.asd</samp> file

 <samp>/home/me/src/foo/foo.asd</samp>.

 </p>

 <div class="lisp">

 <pre class="lisp">(require &quot;asdf&quot;)

 # which is used in :in-order-to

 dependency-def := simple-component-name

                | ( :feature <var>feature-expression</var> dependency-def )

                | ( :version simple-component-name version-specifier )

                | ( :require module-name )

 method-form := (operation-name qual lambda-list &rest body)

 qual := method qualifier?

 feature-expression := keyword

                       | (:and <var>feature-expression</var>*)

                       | (:or <var>feature-expression</var>*)

 to only depend on the specified module on the specific implementation that provides it.

 See <a href="#if_002dfeature_002doption">if-feature-option</a>.

 </p>

 <a name="Using-logical-pathnames"></a>

 <a name="index-logical-pathnames"></a>

 <p>We do not generally recommend the use of logical pathnames,

 </p>

 <a name="Serial-dependencies"></a>

 <a name="index-serial-dependencies"></a>

 <p>If the <code>:serial t</code> option is specified for a module,

 <a name="Source-location-_0028_003apathname_0029"></a>

 <p>The <code>:pathname</code> option is optional in all cases for systems

 defined via <code>defsystem</code>, and generally is unnecessary.  In the

 </li></ul>

 <a name="if_002dfeature-option"></a>

 <a name="index-_003aif_002dfeature-component-option"></a>

 <a name="if_002dfeature_002doption"></a>

 <p>This option allows you to specify a feature expression to be evaluated

 <p>This option was added in ASDF 3.  For more information,

 See <a href="#required_002dfeatures">Required features</a>.

 </p>

 <a name="feature-requirement"></a>

 <h4 class="subsection">6.3.15 feature requirement</h4>

 <p>This requirement was removed in ASDF 3.1.  Please do not use it.  In

 <p>ASDF is designed in an object-oriented way from the ground up.

 Both a system’s structure and the operations that can be performed on systems

 For example, <code>cffi</code> adds support for special FFI description files

 that interface with C libraries and for wrapper files that embed C code in Lisp.

 <code>asdf-jar</code> supports creating Java JAR archives in ABCL.

 <dd><p><code>operate</code> invokes <var>operation</var> on <var>system</var>.

 <code>oos</code> is a synonym for <code>operate</code> (it stands for operate-on-system).

 </p>

 to create the operation object.

 </p>

 Note that dependencies may cause the operation

 to invoke other operations on the system or its components:

 </p>

 <p>If <var>force</var> is <code>:all</code>, then all systems

 are forced to be recompiled even if not modified since last compilation.

 </dd></dl>

 <hr>

 but system <code>foo</code> was previously loaded from <samp>/previous/path/to/foo.asd</samp>

 then <var>locate-system</var> will return the following values:

 </p><ol>

 </li><li> <var>pathname</var> will be <code>#p&quot;/current/path/to/foo.asd&quot;</code>,

 </li><li> <var>previous</var> will be an object of type <code>SYSTEM</code> with

 <code>system-source-file</code> slot value of

 <a name="Shell_002dfriendly-syntax-for-configuration-2"></a>

 <h3 class="section">9.5 Shell-friendly syntax for configuration</h3>

 Entries are separated

 by a <code>;</code> (semicolon) on other platforms (mainly, Windows).

 </p>

 <p>The magic empty entry,

 if it comes in what would otherwise be the first entry in a pair,

 (which has the same effect as if the directory had been repeated).

 </p>

 <hr>

 <a name="Semantics-of-Output-Translations"></a>

 <a name="Semantics-of-Output-Translations-1"></a>

 <code>#+asdf-unicode :encoding #+asdf-unicode :utf-8</code>.

 We recommend that you avoid using unprotected <code>:encoding</code> specifications

 until after ASDF 2.21 or later becomes widespread.

 so you may prudently start using this and other features without such protection.

 </p>

 <p>While it offers plenty of hooks for extension,

 </p></dd></dl>

 <dl>

 <dd><p>A system with name <var>name</var>,

 created by <code>make-instance</code> with extra keys <var>keys</var>

 (e.g. <code>:version</code>),

 is registered as <em>preloaded</em>.

 and if at some point some other system <code>:depends-on</code> it yet no source code is found,

 it is considered as already provided,

 and ASDF will not raise a <code>missing-component</code> error.

 as fasls with either <code>compile-bundle-op</code> or <code>monolithic-compile-bundle-op</code>,

 and want to register systems so that dependencies will work uniformly

 whether you’re using your software from source or from fasl.

 </p></dd></dl>

 <dl>

 <dt><a name="index-register_002dimmutable_002dsystem-1"></a>Function: <strong>register-immutable-system</strong> <em>name &amp;rest keys</em></dt>

 and want to allow users to extend the image with further extension systems,

 for all the systems that came bundled with the image but aren’t

 distributed as source code to regular users.

 <a name="index-immutable-systems-1"></a>

 <h3 class="section">11.4 Some Utility Functions</h3>

 <p>The below functions are not exported by ASDF itself, but by UIOP, available since ASDF 3.

 UIOP provides many, many more utility functions, and we recommend

 </p>

 <dl>

 <dt><a name="index-parse_002dunix_002dnamestring"></a>Function: <strong>parse-unix-namestring</strong> <em>name &amp;key type defaults dot-dot ensure-directory &amp;allow-other-keys</em></dt>

 </p>

 <p>Unix syntax is used whether or not the underlying system is Unix;

 on non-Unix systems it is only usable for relative pathnames.

 A number will extract the corresponding line.

 See the documentation for <code>uiop:access-at</code>.

 as read by the Lisp reader.

 If the <var>count</var> argument is provided,

 it is a maximum count of lines to be read.

 and ensure that ASDF 3 or later is present indeed,

 before they start using ASDF to load anything else.

 the simple solution is just to use code as below in your setup,

 and when it fails, upgrade your implementation or replace its ASDF.

 (see <a href="#Replacing-your-implementation_0027s-ASDF">Replacing your implementation's ASDF</a>):

 <p><code>asdf-ecl</code> and its short-lived successor <code>asdf-bundle</code> are no more,

 having been replaced by code now built into ASDF 3.

 Moreover, the name of the bundle operations has changed since ASDF 3.1.3.

 </p>

 </p>

 <ul>

 <li> <code>fasl-op</code> is now <code>compile-bundle-op</code>

 <code>*standard-output*</code>, so rebinding that stream around calls to

 <code>asdf:operate</code> should redirect all output from ASDF operations.

 </p>

 <hr>

 <a name="ASDF-development-FAQs"></a>

   <a href="http://xach.livejournal.com/">http://xach.livejournal.com/</a>

 </li><li> Francois-Rene Rideau and Robert Goldman:

   “Evolving ASDF: More Cooperation, Less Coordination”, 2010.

   <a href="https://common-lisp.net/project/asdf/doc/ilc2010draft.pdf">https://common-lisp.net/project/asdf/doc/ilc2010draft.pdf</a>

   <a href="https://gitlab.common-lisp.org/asdf/ilc2010">https://gitlab.common-lisp.org/asdf/ilc2010</a>

 </li><li> Francois-Rene Rideau and Spencer Brody:

 <tr><td></td><td valign="top"><a href="#index-_003adefsystem_002ddepends_002don">:defsystem-depends-on</a>:</td><td>&nbsp;</td><td valign="top"><a href="#The-defsystem-grammar">The defsystem grammar</a></td></tr>

 <tr><td></td><td valign="top"><a href="#index-_003adirectory-source-config-directive">:directory source config directive</a>:</td><td>&nbsp;</td><td valign="top"><a href="#Configuration-DSL">Configuration DSL</a></td></tr>

 <tr><td></td><td valign="top"><a href="#index-_003aexclude-source-config-directive">:exclude source config directive</a>:</td><td>&nbsp;</td><td valign="top"><a href="#Configuration-DSL">Configuration DSL</a></td></tr>

 <tr><td></td><td valign="top"><a href="#index-_003aif_002dfeature-component-option">:if-feature component option</a>:</td><td>&nbsp;</td><td valign="top"><a href="#The-defsystem-grammar">The defsystem grammar</a></td></tr>

 <tr><td></td><td valign="top"><a href="#index-_003aignore_002dinvalid_002dentries-source-config-directive">:ignore-invalid-entries source config directive</a>:</td><td>&nbsp;</td><td valign="top"><a href="#Configuration-DSL">Configuration DSL</a></td></tr>

 <tr><td></td><td valign="top"><a href="#index-_003ainclude-source-config-directive">:include source config directive</a>:</td><td>&nbsp;</td><td valign="top"><a href="#Configuration-DSL">Configuration DSL</a></td></tr>

 <tr><td colspan="4"> <hr></td></tr>

 <tr><th><a name="Function-and-Class-Index_fn_letter-M">M</a></th><td></td><td></td></tr>

 <tr><td></td><td valign="top"><a href="#index-make"><code>make</code></a>:</td><td>&nbsp;</td><td valign="top"><a href="#Convenience-Functions">Convenience Functions</a></td></tr>

 <tr><td></td><td valign="top"><a href="#index-merge_002dpathnames_002a"><code>merge-pathnames*</code></a>:</td><td>&nbsp;</td><td valign="top"><a href="#Some-Utility-Functions">Some Utility Functions</a></td></tr>

 <tr><td></td><td valign="top"><a href="#index-module"><code>module</code></a>:</td><td>&nbsp;</td><td valign="top"><a href="#Pre_002ddefined-subclasses-of-component">Pre-defined subclasses of component</a></td></tr>

 <tr><td></td><td valign="top"><a href="#index-monolithic_002dbinary_002dop-_0028obsolete_0029"><code>monolithic-binary-op (obsolete)</code></a>:</td><td>&nbsp;</td><td valign="top"><a href="#What-happened-to-the-bundle-operations">What happened to the bundle operations</a></td></tr>

 <tr><td></td><td valign="top"><a href="#index-system_002ddefsystem_002ddepends_002don"><code>system-defsystem-depends-on</code></a>:</td><td>&nbsp;</td><td valign="top"><a href="#Information-about-system-dependencies">Information about system dependencies</a></td></tr>

 <tr><td></td><td valign="top"><a href="#index-system_002ddepends_002don"><code>system-depends-on</code></a>:</td><td>&nbsp;</td><td valign="top"><a href="#Information-about-system-dependencies">Information about system dependencies</a></td></tr>

 <tr><td></td><td valign="top"><a href="#index-system_002drelative_002dpathname"><code>system-relative-pathname</code></a>:</td><td>&nbsp;</td><td valign="top"><a href="#Miscellaneous-Functions">Miscellaneous Functions</a></td></tr>

 <tr><td></td><td valign="top"><a href="#index-system_002dsource_002ddirectory"><code>system-source-directory</code></a>:</td><td>&nbsp;</td><td valign="top"><a href="#Miscellaneous-Functions">Miscellaneous Functions</a></td></tr>

 <tr><td></td><td valign="top"><a href="#index-system_002dweakly_002ddepends_002don"><code>system-weakly-depends-on</code></a>:</td><td>&nbsp;</td><td valign="top"><a href="#Information-about-system-dependencies">Information about system dependencies</a></td></tr>

 <tr><td colspan="4"> <hr></td></tr>

 <tr><td></td><td valign="top"><a href="#index-_002adefault_002dsource_002dregistry_002dexclusions_002a"><code>*default-source-registry-exclusions*</code></a>:</td><td>&nbsp;</td><td valign="top"><a href="#Search-Algorithm">Search Algorithm</a></td></tr>

 <tr><td></td><td valign="top"><a href="#index-_002afeatures_002a-1"><code>*features*</code></a>:</td><td>&nbsp;</td><td valign="top"><a href="#Introduction">Introduction</a></td></tr>

 <tr><td></td><td valign="top"><a href="#index-_002aimage_002ddump_002dhook_002a"><code>*image-dump-hook*</code></a>:</td><td>&nbsp;</td><td valign="top"><a href="#Resetting-the-ASDF-configuration">Resetting the ASDF configuration</a></td></tr>

 <tr><td></td><td valign="top"><a href="#index-_002aload_002dsystem_002doperation_002a"><code>*load-system-operation*</code></a>:</td><td>&nbsp;</td><td valign="top"><a href="#Convenience-Functions">Convenience Functions</a></td></tr>

 <tr><td></td><td valign="top"><a href="#index-_002anil_002dpathname_002a"><code>*nil-pathname*</code></a>:</td><td>&nbsp;</td><td valign="top"><a href="#Some-Utility-Functions">Some Utility Functions</a></td></tr>

 <tr><td></td><td valign="top"><a href="#index-_002aoldest_002dforward_002dcompatible_002dasdf_002dversion_002a"><code>*oldest-forward-compatible-asdf-version*</code></a>:</td><td>&nbsp;</td><td valign="top"><a href="#Pitfalls-of-the-upgrade-to-ASDF-3">Pitfalls of the upgrade to ASDF 3</a></td></tr>

 <tr><td></td><td valign="top"><a href="#index-_002asource_002dregistry_002dparameter_002a"><code>*source-registry-parameter*</code></a>:</td><td>&nbsp;</td><td valign="top"><a href="#g_t_002asource_002dregistry_002dparameter_002a-variable">*source-registry-parameter* variable</a></td></tr>

 “system directory designators”.

 A <em>system directory designator</em> is a form

 which will be evaluated whenever a system is to be found,

 By “directory”, we mean

 “designator for a pathname with a non-empty DIRECTORY component”.

 </p>

    You can find the latest version of this manual at

 <https://common-lisp.net/project/asdf/asdf.html>.

 Rideau.

    Permission is hereby granted, free of charge, to any person obtaining

 ASDF: Another System Definition Facility

 ****************************************

    This manual describes ASDF, a system definition facility for Common

 Lisp programs and libraries.

    You can find the latest version of this manual at

 <https://common-lisp.net/project/asdf/asdf.html>.

 Rideau.

    Permission is hereby granted, free of charge, to any person obtaining

 * How do I mark a source file to be loaded only and not compiled?::

 * How do I work with readtables?::

 * How can I capture ASDF's output?::

 ASDF development FAQs

 4.2 Configuring ASDF to find your systems -- old style

 ======================================================

 directory pathnames onto the variable 'asdf:*central-registry*'.

    You must configure this variable between the time you load ASDF and

 takes precedence over the above source-registry.(1)

    For example, let's say you want ASDF to find the '.asd' file

 have the following:

      (require "asdf")

    The variable 'asdf:*central-registry*' is thus a list of "system

 directory designators".  A "system directory designator" is a form which

 will be evaluated whenever a system is to be found, and must evaluate to

 for a pathname with a non-empty DIRECTORY component".

    (3) On Windows, you can use Windows shortcuts instead of POSIX

      # which is used in :in-order-to

      dependency-def := simple-component-name

                     | ( :feature FEATURE-EXPRESSION dependency-def )

                     | ( :version simple-component-name version-specifier )

                     | ( :require module-name )

      method-form := (operation-name qual lambda-list &rest body)

      qual := method qualifier?

      feature-expression := keyword

                            | (:and FEATURE-EXPRESSION*)

                            | (:or FEATURE-EXPRESSION*)

 the specific implementation that provides it.  *Note

 if-feature-option::.

 ------------------------------

 We do not generally recommend the use of logical pathnames, especially

 where conventions include the use of underscores, dots or CamelCase in

 pathnames.

 --------------------------

 If the ':serial t' option is specified for a module, ASDF will add

                   (:file "b" :depends-on ("a"))

                   (:file "c" :depends-on ("a" "b")))

 ------------------------------------

 The ':pathname' option is optional in all cases for systems defined via

      that a developer can evaluate a 'defsystem' form from within an

      editor without clobbering its source location)

 ------------------------

 This option allows you to specify a feature expression to be evaluated

    This option was added in ASDF 3.  For more information, *Note

 Required features: required-features.

 6.3.15 feature requirement

 --------------------------

 ASDF is designed in an object-oriented way from the ground up.  Both a

 system's structure and the operations that can be performed on systems

    The key classes in ASDF are 'component' and 'operation'.  A

 'component' represents an individual source file or a group of source

      'operate' invokes OPERATION on SYSTEM.  'oos' is a synonym for

      'operate' (it stands for operate-on-system).

      If FORCE is ':all', then all systems are forced to be recompiled

      even if not modified since last compilation.  If FORCE is 't', then

      To see what 'operate' would do, you can use:

           (asdf:traverse operation-class system-name)

 File: asdf.info,  Node: Predefined operations of ASDF,  Next: Creating new operations,  Prev: Operations,  Up: Operations

      '/current/path/to/foo.asd', but system 'foo' was previously loaded

      from '/previous/path/to/foo.asd' then LOCATE-SYSTEM will return the

      following values:

        3. PATHNAME will be '#p"/current/path/to/foo.asd"',

        4. PREVIOUS will be an object of type 'SYSTEM' with

           'system-source-file' slot value of

 9.5 Shell-friendly syntax for configuration

 ===========================================

    The magic empty entry, if it comes in what would otherwise be the

 first entry in a pair, indicates the splicing of inherited

 File: asdf.info,  Node: Semantics of Output Translations,  Next: Output Caching Results,  Prev: Output Shell-friendly syntax for configuration,  Up: Controlling where ASDF saves compiled files

 reader-conditionalization to protect any ':encoding _encoding_'

 statement, as in '#+asdf-unicode :encoding #+asdf-unicode :utf-8'.  We

 recommend that you avoid using unprotected ':encoding' specifications

 using this and other features without such protection.

    While it offers plenty of hooks for extension, and one such extension

      inspiration (or disinspiration) from what it does in 'header.lisp'

      and 'upgrade.lisp'.

      A system with name NAME, created by 'make-instance' with extra keys

      This function is particularly useful if you distribute your code as

      fasls with either 'compile-bundle-op' or

      that dependencies will work uniformly whether you're using your

      software from source or from fasl.

  -- Function: register-immutable-system name &rest keys

      if you distribute a large body of code as a precompiled image, and

      want to allow users to extend the image with further extension

      systems, but without making thousands of filesystem requests

 The below functions are not exported by ASDF itself, but by UIOP,

 available since ASDF 3.  Some of them have precursors in ASDF 2, but we

  -- Function: parse-unix-namestring name &key type defaults dot-dot

           ensure-directory &allow-other-keys

           documentation for 'uiop:access-at'.

         * If the object is ':forms', the content is captured as a list

           argument is provided, it is a maximum count of lines to be

           read.  We recommend you control the syntax with such macro as

           'uiop:with-safe-io-syntax'.

      ensure that ASDF 3 or later is present indeed, before they start

      using ASDF to load anything else.

      setup, and when it fails, upgrade your implementation or replace

      its ASDF. (*note Replacing your implementation's ASDF::):

           (require "asdf")

 'asdf-ecl' and its short-lived successor 'asdf-bundle' are no more,

 having been replaced by code now built into ASDF 3.  Moreover, the name

    * 'fasl-op' is now 'compile-bundle-op'

    * 'load-fasl-op' is now 'load-bundle-op'

 * How do I mark a source file to be loaded only and not compiled?::

 * How do I work with readtables?::

 * How can I capture ASDF's output?::

 File: asdf.info,  Node: How can I cater for unit-testing in my system?,  Next: How can I cater for documentation generation in my system?,  Prev: Issues with using and extending ASDF to define systems,  Up: Issues with using and extending ASDF to define systems

 'named-readtables:defreadtable'.

 13.6.8 How can I capture ASDF's output?

 ---------------------------------------

 'asdf:operate' should redirect all output from ASDF operations.

 File: asdf.info,  Node: ASDF development FAQs,  Prev: Issues with using and extending ASDF to define systems,  Up: FAQ

 13.7 ASDF development FAQs

      <http://blog.quicklisp.org/> <http://xach.livejournal.com/>

    * Francois-Rene Rideau and Robert Goldman: "Evolving ASDF: More

      Cooperation, Less Coordination", 2010.  This article describes the

      <https://common-lisp.net/project/asdf/doc/ilc2010draft.pdf>

      <https://gitlab.common-lisp.org/asdf/ilc2010>

    * Francois-Rene Rideau and Spencer Brody: "XCVB: an eXtensible

 * :asdf2:                                Introduction.        (line   6)

 * :asdf3:                                Introduction.        (line   6)

 * :build-operation:                      The defsystem grammar.

 * :compile-check:                        Controlling file compilation.

                                                               (line   6)

 * :default-registry source config directive: Configuration DSL.

                                                               (line   6)

 * :defsystem-depends-on:                 The defsystem grammar.

 * :directory source config directive:    Configuration DSL.   (line   6)

 * :exclude source config directive:      Configuration DSL.   (line   6)

 * :if-feature component option:          The defsystem grammar.

 * :ignore-invalid-entries source config directive: Configuration DSL.

                                                               (line   6)

 * :include source config directive:      Configuration DSL.   (line   6)

 * :inherit-configuration source config directive: Configuration DSL.

                                                               (line   6)

 * :require dependencies:                 The defsystem grammar.

 * :tree source config directive:         Configuration DSL.   (line   6)

 * :version:                              The defsystem form.  (line  68)

 * :version <1>:                          The defsystem grammar.

 * :version <2>:                          Common attributes of components.

                                                               (line  23)

 * :weakly-depends-on:                    The defsystem grammar.

 * also-exclude source config directive:  Configuration DSL.   (line   6)

 * around-compile keyword:                Controlling file compilation.

                                                               (line   6)

 * exclude source config directive:       Configuration DSL.   (line   6)

 * ignore-invalid-entries source config directive: Configuration DSL.

                                                               (line   6)

 * immutable systems <1>:                 Miscellaneous Functions.