From 8006da3f229d0227215ccd59cd273edacf72f9ce Mon Sep 17 00:00:00 2001
From: Scott Rifenbark <srifenbark@gmail.com>
Date: Fri, 22 Jul 2016 08:36:09 -0700
Subject: bitbake-user-manual: Added non-existant variable expansion

Fixes [YOCTO #10003]

I added a small paragraph explaining what happens when expansion
of a variable that does not exist occurs.

Signed-off-by: Scott Rifenbark <srifenbark@gmail.com>
---
 doc/bitbake-user-manual/bitbake-user-manual-metadata.xml | 11 +++++++++++
 1 file changed, 11 insertions(+)

(limited to 'doc')

diff --git a/doc/bitbake-user-manual/bitbake-user-manual-metadata.xml b/doc/bitbake-user-manual/bitbake-user-manual-metadata.xml
index fe04103da..ce0e84db0 100644
--- a/doc/bitbake-user-manual/bitbake-user-manual-metadata.xml
+++ b/doc/bitbake-user-manual/bitbake-user-manual-metadata.xml
@@ -86,6 +86,17 @@
                 <link linkend='immediate-variable-expansion'>immediate variable expansion</link>
                 operator (i.e. ":=").
             </para>
+
+            <para>
+                If the variable expansion syntax is used on a variable that
+                does not exist, the string is kept as is.
+                For example, given the following assignment,
+                <filename>BAR</filename> expands to the literal string
+                "${FOO}" as long as <filename>FOO</filename> does not exist.
+                <literallayout class='monospaced'>
+     BAR = "${FOO}"
+                </literallayout>
+            </para>
         </section>
 
         <section id='setting-a-default-value'>
-- 
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