chicken-setup.html

Scheme跨平台编译器

(compile hello2.scm)  <I><FONT COLOR="#B22222">; compile `hello2'
</FONT></I>(install-program 'hello2 <B><FONT COLOR="#BC8F8F">&quot;hello2&quot;</FONT></B>) <I><FONT COLOR="#B22222">; name of the extension and files to be installed
</FONT></I></PRE>
<p>To use it, just run <tt>chicken-setup</tt> in the same directory:</p><pre>$ chicken-setup</pre><p>(Here we omit the extension name)</p><p>Now the program <tt>hello2</tt> will be installed in the same location as the other CHICKEN tools (like <tt>chicken</tt>, <tt>csi</tt>, etc.), which will normally be <tt>/usr/local/bin</tt>.  Note that you need write-permissions for those locations and may have to run <tt>chicken-setup</tt> with administrative rights.</p><p>Uninstallation is just as easy:</p><pre>$ chicken-setup -uninstall hello2</pre><p><tt>chicken-setup</tt> provides a <tt>make</tt> macro, so build operations can be of arbitrary complexity. When running <tt>chicken-setup</tt> with an argument <tt>NAME</tt>, for which no associated file <tt>NAME.setup</tt>, <tt>NAME.egg</tt> or <tt>NAME.scm</tt> exists will ask you to download the extension via HTTP from the default URL <a href="http://www.call-with-current-continuation.org/eggs" class="external">http://www.call-with-current-continuation.org/eggs</a>. You can use the <tt>-host</tt> option to specify an alternative source location. Extensions that are required to compile and/or use the requested extension are downloaded and installed automatically.</p><p>If the given extension name contains a path prefix and the <tt>-host</tt> option is given, then <tt>chicken-setup</tt> can also download and install eggs from an arbitrary HTTP server. Alternatively you can pass a full URL (including the <tt>http://</tt> prefix. Note that no dependency checks are done when downloading eggs directly with the URL syntax.</p><p>Finally a somewhat more complex example: We want to package a syntax extension with additional support code that is to be loaded at run-time of any Scheme code that uses that extension. We create a <em>glass</em> lambda, a procedure with free variables that can be manipulated from outside:</p><PRE>
<I><FONT COLOR="#B22222">;;;; glass.scm
</FONT></I>
(define-macro (glass-lambda llist vars . body)
  <I><FONT COLOR="#B22222">;; Low-level macros are fun!
</FONT></I>  (<B><FONT COLOR="#A020F0">let</FONT></B> ([lvar (gensym)]
	[svar (gensym)] 
	[x (gensym)]
	[y (gensym)] 
	[yn (gensym)] )
    `(<B><FONT COLOR="#A020F0">let</FONT></B> ,(map (<B><FONT COLOR="#A020F0">lambda</FONT></B> (v) (list v #f)) vars)
       (<B><FONT COLOR="#A020F0">define</FONT></B> (,svar ,x . ,y)
	 (<B><FONT COLOR="#A020F0">let*</FONT></B> ([,yn (pair? ,y)]
		[,y (<B><FONT COLOR="#A020F0">and</FONT></B> ,yn (car ,y))] )
	   (<B><FONT COLOR="#A020F0">case</FONT></B> ,x
	     ,@(map (<B><FONT COLOR="#A020F0">lambda</FONT></B> (v)
		      `([,v] (<B><FONT COLOR="#A020F0">if</FONT></B> ,yn 
				 (<B><FONT COLOR="#A020F0">set!</FONT></B> ,v ,y)
				 ,v) ) )
		    vars)
	     (<B><FONT COLOR="#A020F0">else</FONT></B> (error <B><FONT COLOR="#BC8F8F">&quot;variable not found&quot;</FONT></B> ,x)) ) ) )
       (<B><FONT COLOR="#A020F0">define</FONT></B> ,lvar (<B><FONT COLOR="#A020F0">lambda</FONT></B> ,llist ,@body))
       (extend-procedure ,lvar ,svar) ) ) )
</PRE>
<p>Here some support code that needs to be loaded at runtime:</p><PRE>
<I><FONT COLOR="#B22222">;;;; glass-support.scm
</FONT></I>
(require-extension lolevel)