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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">I think immediate expansion is what I’ll need to use, thanks for the tip. That at least brings the invocation down to once per run. Unfortunately, the variable
doesn’t seem to get filled in when I change to immediate expansion.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">def testFunc(bb, d):<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> print( bb.data.getVar("PN", d, True) )<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> return "e1"<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">EXTERNPV := "${@testFunc(bb, d)}"<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Now only prints the package name once, but using –e, I don’t see the variable EXTERNPV at all.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> Christopher Larson [mailto:kergoth@gmail.com]
<br>
<b>Sent:</b> Wednesday, April 18, 2012 4:07 PM<br>
<b>To:</b> Daniel Lazzari<br>
<b>Cc:</b> 'bitbake-devel@lists.openembedded.org' (bitbake-devel@lists.openembedded.org)<br>
<b>Subject:</b> Re: [bitbake-devel] python function used in variable expansion called multiple times per recipe<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Helvetica","sans-serif"">${@} contents are evaluated when the variable is expanded. Variables are expanded when they're used, much in the way they are in makefiles. Use := to force immediate expansion,
or don't use ${@} (alternatives, anonymous python function or event handler).<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">-- <o:p></o:p></p>
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<p class="MsoNormal">Christopher Larson<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p><span style="color:#A0A0A8">On Wednesday, April 18, 2012 at 2:21 PM, Daniel Lazzari wrote:<o:p></o:p></span></p>
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<p class="MsoNormal">Hi everyone,<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">I've been wrestling with this problem for over a day now so I figured it's time to call in the cavalry.<o:p></o:p></p>
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<p class="MsoNormal">I have a class in our layer that needs to fill in a variable (EXTERNPV) with information about svn externals in a project. This process can be very time consuming and resource intensive so I would prefer that it only happen once per run.
Unfortunately, it seems to run 5 times for each recipe that inherits the class. You can easily duplicate the behavior I see with the following:<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">def testFunc(bb, d):<o:p></o:p></p>
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<p class="MsoNormal">print( bb.data.getVar("PN", d, True) )<o:p></o:p></p>
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<p class="MsoNormal">return "e1"<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">EXTERNPV = "${@testFunc(bb, d)}"<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Am I doing something wrong? Is there some assignment operator I can use to ensure this only has to be done once? Or maybe a variable flag?<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">As always, I very much appreciate the help.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Dan Lazzari Jr.<o:p></o:p></p>
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<p class="MsoNormal">Firmware Engineer<o:p></o:p></p>
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<p class="MsoNormal"><a href="mailto:dlazzari@leapfrog.com">dlazzari@leapfrog.com</a><o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">_______________________________________________<o:p></o:p></p>
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<p class="MsoNormal">bitbake-devel mailing list<o:p></o:p></p>
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<p class="MsoNormal"><a href="mailto:bitbake-devel@lists.openembedded.org">bitbake-devel@lists.openembedded.org</a><o:p></o:p></p>
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<p class="MsoNormal"><a href="http://lists.linuxtogo.org/cgi-bin/mailman/listinfo/bitbake-devel">http://lists.linuxtogo.org/cgi-bin/mailman/listinfo/bitbake-devel</a><o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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