05/06: doc: Clarify how to use the '#:python' parameter.

[Ludovic Courtès]

civodul pushed a commit to branch master
in repository guix.

commit 8a46205b418605bcbd64b12426239f10c2113ff4
Author: Chris Marusich <address@hidden>
Date:   Wed Mar 30 02:43:16 2016 -0700

    doc: Clarify how to use the '#:python' parameter.
    
    * doc/guix.texi (Build Systems): Clearly distinguish between the package 
that
    provides the Python interpreter for the build and the package that is to be
    built.  Also, mention why one might want to use a specific Python version.
    
    Signed-off-by: Ludovic Courtès <address@hidden>
---
 doc/guix.texi |    7 +++++--
 1 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/doc/guix.texi b/doc/guix.texi
index 1a7f188..7a27ab3 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -2854,8 +2854,11 @@ For packages that install stand-alone Python programs 
under @code{bin/},
 it takes care of wrapping these programs so that their @code{PYTHONPATH}
 environment variable points to all the Python libraries they depend on.
 
-Which Python package is used can be specified with the @code{#:python}
-parameter.
+Which Python package is used to perform the build can be specified with
+the @code{#:python} parameter.  This is a useful way to force a package
+to be built for a specific version of the Python interpreter, which
+might be necessary if the package is only compatible with a single
+interpreter version.
 @end defvr
 
 @defvr {Scheme Variable} perl-build-system