On 03/08/2012 07:03 AM, Michał Górny wrote:
>>
>> Someone suggested using a standard shebang the last time this came
>> up, and if I remember correctly it was one of the least-disagreeable
>> solutions proposed. We could of course define our own custom format,
>> but I think something like,
>>
>>     #!/usr/bin/eapi5
>>
>> would be perfect if we could hand off the interpretation of the
>> ebuild to that program. That solves the problem with new bash
>> features, too, since you could point that command at a specific
>> version.
>
> And what would /usr/bin/eapi5 do? Are you suggesting misusing shebang
> or making ebuilds PM-centric?
>

I was saying that I'd prefer a more-standard use of the shebang (if 
possible), rather than defining our own header comment syntax. Either 
way I think the second option is cleaner than regular expressions.

Right now, we're guaranteed the features of bash-3.2. I guess we 
actually use whatever is executing ebuild.sh to source them. But we need 
to interpret the ebuild file with something: we might as well put *that* 
in the shebang, since that's what it's for.

So if we were to do this with an ebuild right now, we'd add,

   #!/usr/bin/eapi4

to the header, and instead of sourcing the ebuild with whatever 
ebuild.sh is using, we would run it with 'eapi4' and pass whatever we 
need back and forth. Or maybe ebuild.sh would reload itself using 
'eapi4'. If any of that makes sense, the PMS would just need to specify 
some requirements on the shebang command.