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<div><h1>prefixPath -- absolute locations of Macaulay2 files</h1>
<div class="single"><h2>Description</h2>
<div><p>The absolute location of a Macaulay2 file can be obtained by concatenating three components: (a) the prefix, which is one of the members of the list <a href="_prefix__Path.html" title="absolute locations of Macaulay2 files">prefixPath</a>; (b) the relative location of the directory containing the file, as recorded in the hash table <a href="_current__Layout.html" title="relative locations of Macaulay2 files">Layout</a>; and (c) the base name of the file. The value of <a href="_prefix__Path.html" title="absolute locations of Macaulay2 files">prefixPath</a> is used by <a href="_install__Package.html" title="load and install a package and its documentation ">installPackage</a> when determining how to direct documentation hyperlinks from one package to another, provided the option <a href="___Absolute__Links.html" title="name for an optional argument">AbsoluteLinks</a> is set to <a href="_true.html" title="">true</a>.</p>
<p>The initial value of <a href="_prefix__Path.html" title="absolute locations of Macaulay2 files">prefixPath</a> contains just the following two optional items. If the variable <a href="_prefix__Directory.html" title="the prefix directory">prefixDirectory</a> was given a non-null value initially or by a <tt>-e</tt> command line argument, then it will be the last element of <a href="_prefix__Path.html" title="absolute locations of Macaulay2 files">prefixPath</a>. If the <tt>-q</tt> option was not given on the command line used to invoke Macaulay2, then the value of <tt>applicationDirectory()|"local/"</tt> will be the first element of <a href="_prefix__Path.html" title="absolute locations of Macaulay2 files">prefixPath</a>. No attempt is made to synchronize the value of <a href="_prefix__Path.html" title="absolute locations of Macaulay2 files">prefixPath</a> with the values of <a href="_prefix__Directory.html" title="the prefix directory">prefixDirectory</a> and of <tt>applicationDirectory()</tt>, which may change.</p>
<p>When running a newly compiled version of Macaulay2, adding something like <tt>-E 'prefixDirectory="/usr/"'</tt> to the command line is a good way to direct hyperlinks created by <a href="_install__Package.html" title="load and install a package and its documentation ">installPackage</a> to the documentation provided by an older copy of Macaulay2 installed with the prefix <tt>/usr/</tt>, and that, in turn, is easily done within emacs by the keystroke sequence <tt>CTRL-U f12</tt>, which offers you a chance to edit the command line.</p>
<p>The initial value of <a href="_prefix__Path.html" title="absolute locations of Macaulay2 files">prefixPath</a> described above can be overridden by the user's <a href="_initialization_spfile.html" title="">initialization file</a>).</p>
<p>The list <a href="_prefix__Path.html" title="absolute locations of Macaulay2 files">prefixPath</a> should be distinguished from the list <a href="_path.html" title="list of directories to look in">path</a>, which is used to locate files to be loaded, by functions such as <a href="_search__Path_lp__List_cm__String_rp.html" title="search a path for a file">searchPath</a>, <a href="_load.html" title="read Macaulay2 commands">load</a>, <a href="_load__Package.html" title="load a package">loadPackage</a>, and <a href="_needs__Package.html" title="load a package if not already loaded">needsPackage</a>.</p>
<p>The following example shows the list of places where we might find the source code of a package called <tt>Foo</tt> after it has been installed by <a href="_install__Package.html" title="load and install a package and its documentation ">installPackage</a>.</p>
<table class="examples"><tr><td><pre>i1 : stack apply(prefixPath, p -> p | Layout#1#"packages" | "Foo.m2")
o1 = /builddir/build/BUILD/Macaulay2-1.3.1-r10737/StagingArea/
/builddir/build/BUILD/Macaulay2-1.3.1-r10737/StagingArea/
/builddir/build/BUILD/Macaulay2-1.3.1-r10737/StagingArea/
------------------------------------------------------------------------
common/share/Macaulay2/Foo.m2
share/Macaulay2/Foo.m2
i686-Linux-Fedora-15/share/Macaulay2/Foo.m2</pre>
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<p>This example shows the list of places where we might reasonably find the html file documenting a function named <tt>bar</tt> in a package called <tt>Foo</tt>.</p>
<table class="examples"><tr><td><pre>i2 : stack apply(prefixPath, p -> p | replace("PKG","Foo",Layout#1#"packagehtml") | "bar.html")
o2 = /builddir/build/BUILD/Macaulay2-1.3.1-r10737/StagingArea/
/builddir/build/BUILD/Macaulay2-1.3.1-r10737/StagingArea/
/builddir/build/BUILD/Macaulay2-1.3.1-r10737/StagingArea/
------------------------------------------------------------------------
common/share/doc/Macaulay2/Foo/html/bar.html
share/doc/Macaulay2/Foo/html/bar.html
i686-Linux-Fedora-15/share/doc/Macaulay2/Foo/html/bar.html</pre>
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<p>This example shows the list of places where we might reasonably find the info file documenting a package called <tt>Foo</tt>.</p>
<table class="examples"><tr><td><pre>i3 : stack apply(prefixPath, p -> p | Layout#1#"info" | "Foo.info")
o3 = /builddir/build/BUILD/Macaulay2-1.3.1-r10737/StagingArea/
/builddir/build/BUILD/Macaulay2-1.3.1-r10737/StagingArea/
/builddir/build/BUILD/Macaulay2-1.3.1-r10737/StagingArea/
------------------------------------------------------------------------
common/share/info/Foo.info
share/info/Foo.info
i686-Linux-Fedora-15/share/info/Foo.info</pre>
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<div class="single"><h2>See also</h2>
<ul><li><span><a href="_command__Line.html" title="the command line arguments">commandLine</a> -- the command line arguments</span></li>
<li><span><a href="___Invoking_spthe_spprogram.html" title="">Invoking the program</a></span></li>
<li><span><a href="_application__Directory.html" title="the path to the user's application directory">applicationDirectory</a> -- the path to the user's application directory</span></li>
<li><span><a href="_prefix__Directory.html" title="the prefix directory">prefixDirectory</a> -- the prefix directory</span></li>
<li><span><a href="_path.html" title="list of directories to look in">path</a> -- list of directories to look in</span></li>
<li><span><a href="_search__Path_lp__List_cm__String_rp.html" title="search a path for a file">searchPath</a> -- search a path for a file</span></li>
<li><span><a href="_load.html" title="read Macaulay2 commands">load</a> -- read Macaulay2 commands</span></li>
<li><span><a href="_load__Package.html" title="load a package">loadPackage</a> -- load a package</span></li>
<li><span><a href="_needs__Package.html" title="load a package if not already loaded">needsPackage</a> -- load a package if not already loaded</span></li>
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<div class="waystouse"><h2>For the programmer</h2>
<p>The object <a href="_prefix__Path.html" title="absolute locations of Macaulay2 files">prefixPath</a> is <span>a <a href="___List.html">list</a></span>.</p>
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