[Boost-build] bbv2 Custom requirements rule, howto?

From: Roland Schwarz (roland.schwarz_at_[hidden])
Date: 2006-07-24 06:45:40

In bbv1 it was possible to have custom requirements rule which had the 
signature:

rule my-requirements ( toolset variant : subvariant-path properties * )

Is there something similar available in bbv2?

Or is there a different(similar) mechanism available in bbv2?
I used this to conditionally calculate library and include directives 
from environment variables.

Regards,
Roland