[yocto] which yocto doc explains bitbake assignment variations?

[Robert P. J. Day]

On Thu, 29 Mar 2012, Rudolf Streif wrote:

> 1. yes, = will always override any prior ?= or ??= and any subsequent ?= or ??= will not change the
> setting anymore.
> 2. yes, a ?= following a ??= will set the variable. Only a = will be override the setting of the ?=.
> Any following ?= and ??= will not change the setting.
>
> 3. yes, a ?= or = following a ??= will set the variable.
>
>
> Just try it. Put a variable (FOO) in local.conf and use bitbake -e | grep FOO
>
> FOO ??= "bar"
> FOO ?= "barbar"

  thanks, i've already been testing numerous variations just so i'm
absolutely convinced i understand it.

rday

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Robert P. J. Day                                 Ottawa, Ontario, CANADA
                        http://crashcourse.ca

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