[PATCH v9 3/7] env: Allow U-Boot scripts to be placed in a .env file

Wolfgang Denk wd at denx.de
Thu Oct 21 17:12:26 CEST 2021

Dear Marek,

In message <20211021152831.15524883 at thinkpad> you wrote:
> > I think =+ will confuse far more people than + as last character of var

I still fail to see why '=+' could be confusing if properly
documented to be the append operator.

I mean, it is not a new invention of mine.

OpenEmbedded / Yocto uses '=+' a lot, like in


	PACKAGES =+ "${PN}-misc"

Actually they use both '+=' and '=+', like


> > name working weirdly. But I also think that + should be supported as
> > last character. Therefore I propose backslash escaping in variable name,
> > i.e.
> >   var+=value
> > appends value to var, while
> >   var\+=value
> > sets variable with name "var+"

Yes, this is yet another alternative for handling this problem.

> Also, I think that it would be better if spaces and tabs were allowed
> to indent the .env file, i.e.
> 	var_a	=	3
> 	var_bcd	=	7
> should set "var_a" to "3", "var_bcd" to "7".

Why not...

In the end it boils down that the file format should be properly
defined and have a clear syntax description.  Apparently the
"<name>=<value>\0" format as used in U-Boot persistent storage
should not be taken literally here.

Best regards,

Wolfgang Denk

DENX Software Engineering GmbH,      Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
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