Re: bug#7944: Should AM_PATH_PYTHON call AC_ARG_VAR?

[Ralf Wildenhues]

* Stefano Lattarini wrote on Tue, Feb 15, 2011 at 12:37:58AM CET:
> On Monday 14 February 2011, Ralf Wildenhues wrote:
> > * Stefano Lattarini wrote on Mon, Feb 14, 2011 at 12:35:17PM CET:
> > > On Friday 11 February 2011, Ralf Wildenhues wrote:
> > > > 
> > > > There are a couple of things that I think could be better.  One sentence
> > > > as a paragraph on its own isn't too pretty.  The PYTHON override doesn't
> > > > seem to be the most important thing to me, so I'd put it last not first.
> > > > This would be in line with how autoconf.texi documents many macros:
> > > > cache and override variables are listed late.  Also, I'd document that
> > > > the PYTHON variable is set by the macro.  Ahh, that is already done,
> > > > further down in the text.  I think the mention of override could be
> > > > placed there as well.
> > > > 
> > > > So, how about this instead?  Feel free to squash in and push if you
> > > > agree.
> > > >
> > > Hmmm... is the diff you posted incomplete, or am I missing something?
> > > I'll refrain from pushing the patch until this issue is clarified.
> > 
> > I think the diff was complete in the sense that all my intended changes
> > were shown,
> >
> Oh.  I thought it was incomplete in the sense that it didn't address some
> of the issues you had brought up (``The PYTHON override doesn't seem to
> be the most important thing to me, so I'd put it last not first'', ``One
> sentence as a paragraph on its own isn't too pretty'', etc,).  I think
> we are experiencing a communication problem here; i.e., I can't understand
> whether I'm supposed to address those issues myself, or whether you think
> that they are secondary, your squash-in diff is enough, and I should push
> after having just applied it.  Could you please clarify?  Thanks.

Sorry, I'm probably just making myself not clear.  Here's a patch that I
would squash in on top of your patch, and that I think addresses all
issues that I mention in my review.  It basically reverses the doc part
of your patch and then applies the diff I posted earlier.

Thanks for your patience,
Ralf

diff --git a/doc/automake.texi b/doc/automake.texi
index fd9d33e..091d7a2 100644
--- a/doc/automake.texi
+++ b/doc/automake.texi
@@ -7632,24 +7632,19 @@ Python
 installed (see the definitions of @code{pythondir} and
 @code{pkgpythondir} below).
 
address@hidden AM_PATH_PYTHON (@ovar{version}, @ovar{action-if-found}, 
@ovar{action-if-not-found})
address@hidden AM_PATH_PYTHON (@ovar{version}, @ovar{action-if-found}, @
+  @ovar{action-if-not-found})
 
-Search for a Python interpreter on the system.  The user can force the
-choice with the configuration variable @env{PYTHON}.
+Search for a Python interpreter on the system.  This macro takes three
+optional arguments.  The first argument, if present, is the minimum
+version of Python required for this package: @code{AM_PATH_PYTHON}
+will skip any Python interpreter that is older than @var{version}.
+If an interpreter is found and satisfies @var{version}, then
address@hidden is run.  Otherwise, @var{action-if-not-found} is
+run.
 
-This macro takes three optional arguments.
-
-The first argument, if present, is the minimum version of Python required
-for this package; @code{AM_PATH_PYTHON} will skip any Python interpreter
-that is older than @var{version}.  Note that, if @env{PYTHON} was specified
-by the user, the version check will still take place, but no other Python
-interpreter will be tried if that fails.
-
-If an interpreter is found and satisfies @var{version} (which, in case
address@hidden is empty or unspecified, means @emph{any} interpreter), then
address@hidden is run.  Otherwise, @var{action-if-not-found} is run.
-If @var{action-if-not-found} is not specified, as in the following example
-, the default is to abort @command{configure}.
+If @var{action-if-not-found} is not specified, as in the following
+example, the default is to abort @command{configure}.
 
 @example
 AM_PATH_PYTHON([2.2])
@@ -7664,6 +7659,9 @@ Python
 AM_PATH_PYTHON([2.5],, [:])
 @end example
 
+If the @env{PYTHON} variable is set when @code{AM_PATH_PYTHON} is
+called, then that will be the only Python interpreter that is tried.
+
 @code{AM_PATH_PYTHON} creates the following output variables based on
 the Python installation found during configuration.
 @end defmac
@@ -7679,8 +7677,8 @@ Python
 as follows.
 
 @example
-  AM_PATH_PYTHON(,, [:])
-  AM_CONDITIONAL([HAVE_PYTHON], [test "$PYTHON" != :])
+AM_PATH_PYTHON(,, [:])
+AM_CONDITIONAL([HAVE_PYTHON], [test "$PYTHON" != :])
 @end example
 
 @item PYTHON_VERSION