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Message-ID: <2bad5b8490f2b1e2aad09127fb1ed2d8efeb7438.camel@linuxfoundation.org>
Subject: Re: [bitbake-devel] more nitpickery: difference between d.getVar() and d.expand()?
From: "Richard Purdie" <richard.purdie@linuxfoundation.org>
To: bitbake-devel@lists.openembedded.org
Date: Tue, 19 May 2020 11:58:44 +0100
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On Tue, 2020-05-05 at 09:27 -0400, Robert P. J. Day wrote:
>   no, wait, hear me out :-). still crawling through BB user manual,
> section 3.5.2, talks about using d.getVar("X") "or for more
> complicated expressions, use d.expand()".
> 
>   fair enough, but it seems like a lot of the code bounces back and
> forth when getting the value of a simple variable, as in:
> 
>   libdir = d.getVar("libdir")
>   libdir = d.expand("${libdir}")
> 
> given that d.getVar() by default expands the value, is there some
> difference between the two statements above when specifically
> accessing a single variable in the data dictionary?

No, there is no difference. I'd usually suggest getVar for a single
variable and expand for an expression.

Cheers,

Richard