Re: [gentoo-dev] RFD: EAPI specification in ebuilds

["Walter Dnes" <waltdnes@waltdnes.org>]

On Wed, Mar 07, 2012 at 09:41:02PM +0100, Ulrich Mueller wrote

> Written in a more formal way, appropriate for a specification:
> - Ebuilds must contain at most one EAPI assignment statement.
> - It must occur within the first N lines of the ebuild (N=10 and N=30
>   have been suggested).
> - The statement must match the following regular expression (extended
>   regexp syntax):
>   ^[ \t]*EAPI=(['"]?)([A-Za-z0-9._+-]*)\1[ \t]*(#.*)?$
> 
> Note: The first and the third point are already fulfilled by all
> ebuilds in the Portage tree. The second point will require very few
> ebuilds to be changed (9 packages for N=10, or 2 packages for N=30).

  The second point could be rendered moot with a little sanity checking
like so...

#!/bin/bash
counter=`grep -c "^EAPI=" ${1}`
if [ ${counter} -eq 0 ]; then
#  <call routine for processing EAPI 0>
   exit
elif [ ${counter} -gt 1 ]; then
   echo "***ERROR*** only 1 line allowed beginning with EAPI="
   exit
else
#  <parse value of EAPI and call appropriate ebuild parser version>
   exit
fi

  This treats the EAPI statement as a declaration, and doesn't care
where it shows up in the file.  I'm assuming no leading blanks in front
of "EAPI".

-- 
Walter Dnes <waltdnes@waltdnes.org>