plplot-devel

[Plplot-devel] Use $(VAR) instead of @VAR@ in Makefile.am

[Rafael L. <lab...@ps...>]

In doing my last changes, I noticed that in many Makefiles.am, constructs
like @MATWRAP@ and @MKOCTFILE@ are used.  This is bad practice.  Use
$(MATWRAP) and $(MKOCTFILE) instead, which is the standard, advised style.

The reason for this is simple: variables could be replaced in the invocation
of make, like this: 

    make MKOCTFILE=my-mkoctfile

Using the construct @VARIABLE@ prevents doing that.

This is not a particular problem in the PLplot project, since I guess that
people barely need the variable substitution feature.  However, try to
follow the good usage rule, please. 

I will fix those @VAR@ instances in the various Makefile.am, eventually.

-- 
Rafael

Re: [Plplot-devel] Use $(VAR) instead of @VAR@ in Makefile.am

[Alan W. I. <ir...@be...>]

On Wed, 19 Feb 2003, Rafael Laboissiere wrote:

> In doing my last changes, I noticed that in many Makefiles.am, constructs
> like @MATWRAP@ and @MKOCTFILE@ are used.  This is bad practice.  Use
> $(MATWRAP) and $(MKOCTFILE) instead, which is the standard, advised style.

I agree.  A lot of those crept through from the old way of doing things, and
I appreciate your willingness to clean it up, and I will try not to make
more problems like this.

Another part of the form I believe we should be careful of is continuations
(especially in lists).  I noticed one or two problems with that recently. I
don't know whether these were leftovers from the old days or something that
had been recently introduced in error. The old Makefile standard was always
to continue with a "space \" at the end of the line followed by a tab at the
start of the continued line.  It doesn't matter to GNU make, but I believe
it may be important to maintain this old continuation style for
cross-platform use. For 5.1.0 we demanded everybody use GNU make, but with
the autotools approach our users are supposed to be able to use native make
again, and some versions may have this constraint on their continuation
style.  This of course would not matter if automake parsed and massaged the
continuations, but I don't think it does.  Last time I looked it just passed
them through with the continuation style imposed in the Makefile.am file.

Alan
__________________________
Alan W. Irwin
email: ir...@be...
phone: 250-727-2902

Astronomical research affiliation with Department of Physics and Astronomy,
University of Victoria (astrowww.phys.uvic.ca).

Programming affiliations with the Canadian Centre for Climate Modelling and
Analysis (www.cccma.bc.ec.gc.ca) and the PLplot scientific plotting software
package (plplot.org).

__________________________

Linux-powered Science
__________________________

Re: [Plplot-devel] Use $(VAR) instead of @VAR@ in Makefile.am

[Maurice L. <mj...@ga...>]

Rafael Laboissiere writes:
 > In doing my last changes, I noticed that in many Makefiles.am, constructs
 > like @MATWRAP@ and @MKOCTFILE@ are used.  This is bad practice.  Use
 > $(MATWRAP) and $(MKOCTFILE) instead, which is the standard, advised style.
 > 
 > The reason for this is simple: variables could be replaced in the invocation
 > of make, like this: 
 > 
 >     make MKOCTFILE=my-mkoctfile
 > 
 > Using the construct @VARIABLE@ prevents doing that.
 > 
 > This is not a particular problem in the PLplot project, since I guess that
 > people barely need the variable substitution feature.  However, try to
 > follow the good usage rule, please. 

I *thought* I noticed some odd behaviors when testing plplot using this style
of build, weeks ago.  Glad you got to the bottom of it.

-- 
Maurice LeBrun    mj...@ga...
Research Organization for Information Science and Technology of Japan (RIST)