<?xml version="1.0"?>
<!--
Copyright The SCons Foundation

This file is processed by the bin/SConsDoc.py module.
See its __doc__ string for a discussion of the format.
-->

<!DOCTYPE sconsdoc [
<!ENTITY % scons SYSTEM '../../doc/scons.mod'>
%scons;
<!ENTITY % builders-mod SYSTEM '../../doc/generated/builders.mod'>
%builders-mod;
<!ENTITY % functions-mod SYSTEM '../../doc/generated/functions.mod'>
%functions-mod;
<!ENTITY % tools-mod SYSTEM '../../doc/generated/tools.mod'>
%tools-mod;
<!ENTITY % variables-mod SYSTEM '../../doc/generated/variables.mod'>
%variables-mod;
]>

<sconsdoc xmlns="http://www.scons.org/dbxsd/v1.0"
          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:schemaLocation="http://www.scons.org/dbxsd/v1.0 http://www.scons.org/dbxsd/v1.0/scons.xsd">


<scons_function name="FindPathDirs">
<arguments signature="global">
(variable)
</arguments>
<summary>
<para>
Returns a function
(actually a callable Python object)
intended to be used as the
<varname>path_function</varname>
of a Scanner object.
The returned object will look up the specified
<varname>variable</varname>
in a construction environment
and treat the construction variable's value as a list of
directory paths that should be searched
(like
&cv-link-CPPPATH;,
&cv-link-LIBPATH;,
etc.).
</para>

<para>
Note that use of
&f-FindPathDirs;
is generally preferable to
writing your own
<varname>path_function</varname>
for the following reasons:
1) The returned list will contain all appropriate directories
found in source trees
(when
&f-link-VariantDir;
is used)
or in code repositories
(when
&f-Repository;
or the
<option>-Y</option>
option are used).
2) scons will identify expansions of
<varname>variable</varname>
that evaluate to the same list of directories as,
in fact, the same list,
and avoid re-scanning the directories for files,
when possible.
</para>

<para>
Example:
</para>

<example_commands>
def my_scan(node, env, path, arg):
    # Code to scan file contents goes here...
    return include_files

scanner = Scanner(name = 'myscanner',
                  function = my_scan,
                  path_function = FindPathDirs('MYPATH'))
</example_commands>
</summary>
</scons_function>

</sconsdoc>
