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authorScott Rifenbark <srifenbark@gmail.com>2016-07-21 11:02:52 -0700
committerRichard Purdie <richard.purdie@linuxfoundation.org>2016-08-02 15:22:15 +0100
commita3a7ddf120b9ab893ab1cbdbcb6ed28c15abe5e9 (patch)
tree7e9449fed09e8751978b212b63ca9dd8d6f45caa /bitbake/doc
parenteb282b797e07f807f8c9c86439c8c906b78f9412 (diff)
downloadopenembedded-core-contrib-a3a7ddf120b9ab893ab1cbdbcb6ed28c15abe5e9.tar.gz
bitbake: bitbake-user-manual: Updated the "Inline Python Variable Expansion" section.
Fixes [YOCTO #9984] Added a small note to the bottom to help clarify. (Bitbake rev: 64bf49826088c56b739ed971251f05b4564c712e) Signed-off-by: Scott Rifenbark <srifenbark@gmail.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Diffstat (limited to 'bitbake/doc')
-rw-r--r--bitbake/doc/bitbake-user-manual/bitbake-user-manual-metadata.xml17
1 files changed, 16 insertions, 1 deletions
diff --git a/bitbake/doc/bitbake-user-manual/bitbake-user-manual-metadata.xml b/bitbake/doc/bitbake-user-manual/bitbake-user-manual-metadata.xml
index 436abd5ec1..f7b541d9d1 100644
--- a/bitbake/doc/bitbake-user-manual/bitbake-user-manual-metadata.xml
+++ b/bitbake/doc/bitbake-user-manual/bitbake-user-manual-metadata.xml
@@ -316,7 +316,7 @@
</literallayout>
<note>
It is never necessary to use "+=" together with "_append".
- The following sequence of assignments appepnds "barbaz" to
+ The following sequence of assignments appends "barbaz" to
<filename>FOO</filename>:
<literallayout class='monospaced'>
FOO_append = "bar"
@@ -401,6 +401,21 @@
PN = "${@bb.parse.BBHandler.vars_from_file(d.getVar('FILE', False),d)[0] or 'defaultpkgname'}"
PV = "${@bb.parse.BBHandler.vars_from_file(d.getVar('FILE', False),d)[1] or '1.0'}"
</literallayout>
+ <note>
+ Inline Python expressions work just like variable expansions
+ insofar as the "=" and ":=" operators are concerned.
+ Given the following assignment, <filename>foo()</filename>
+ is called each time <filename>FOO</filename> is expanded:
+ <literallayout class='monospaced'>
+ FOO = "${@foo()}"
+ </literallayout>
+ Contrast this with the following immediate assignment, where
+ <filename>foo()</filename> is only called once, while the
+ assignment is parsed:
+ <literallayout class='monospaced'>
+ FOO := "${@foo()}"
+ </literallayout>
+ </note>
</para>
</section>