- How do I keep my $VERSION up to date without resetting it manually?
-
Often you want to manually set the $VERSION in the main module
distribution because this is the version that everybody sees on CPAN and maybe you want to customize it a bit. But for all the other
modules in your dist, $VERSION is really just bookkeeping and all that's
important is it goes up every time the module is changed. Doing this
by hand is a pain and you often forget.
-
Simplest way to do it automatically is to use your version control
system's revision number (you are using version control, right?).
-
In CVS, RCS and SVN you use $Revision$ (see the documentation of your
version control system for details) writing it like so:
-
$VERSION = sprintf "%d.%03d", q$Revision$ =~ /(\d+)/g;
-
Every time the file is checked in the $Revision$ will be updated,
updating your $VERSION.
-
In CVS version 1.9 is followed by 1.10. Since CPAN compares version
numbers numerically we use a sprintf() to convert 1.9 to 1.009 and
1.10 to 1.010 which compare properly.
-
If branches are involved (ie. $Revision: 1.5.3.4$) its a little more
complicated.
-
# must be all on one line or MakeMaker will get confused.
$VERSION = do { my @r = (q$Revision$ =~ /\d+/g); sprintf "%d."."%03d" x $#r, @r };
- What's this META.yml thing and how did it get in my MANIFEST?!
-
META.yml is a module meta-data file pioneered by Module::Build and
automatically generated as part of the 'distdir' target (and thus
'dist'). See Module Meta-Data in the ExtUtils::MakeMaker manpage.
-
To shut off its generation, pass the NO_META flag to WriteMakefile().
- How to I prevent ``object version X.XX does not match bootstrap parameter Y.YY'' errors?
-
XS code is very sensitive to the module version number and will
complain if the version number in your Perl module doesn't match. If
you change your module's version # without reruning Makefile.PL the old
version number will remain in the Makefile causing the XS code to be built
with the wrong number.
-
To avoid this, you can force the Makefile to be rebuilt whenever you
change the module containing the version number by adding this to your
WriteMakefile() arguments.
-
depend => { '$(FIRST_MAKEFILE)' => '$(VERSION_FROM)' }
- How do I make two or more XS files coexist in the same directory?
-
Sometimes you need to have two and more XS files in the same package.
One way to go is to put them into separate directories, but sometimes
this is not the most suitable solution. The following technique allows
you to put two (and more) XS files in the same directory.
-
Let's assume that we have a package Cool::Foo, which includes
Cool::Foo and Cool::Bar modules each having a separate XS
file. First we use the following Makefile.PL:
-
use ExtUtils::MakeMaker;
-
WriteMakefile(
NAME => 'Cool::Foo',
VERSION_FROM => 'Foo.pm',
OBJECT => q/$(O_FILES)/,
# ... other attrs ...
);
-
Notice the OBJECT attribute. MakeMaker generates the following
variables in Makefile:
-
# Handy lists of source code files:
XS_FILES= Bar.xs \
Foo.xs
C_FILES = Bar.c \
Foo.c
O_FILES = Bar.o \
Foo.o
-
Therefore we can use the O_FILES variable to tell MakeMaker to use
these objects into the shared library.
-
That's pretty much it. Now write Foo.pm and Foo.xs, Bar.pm
and Bar.xs, where Foo.pm bootstraps the shared library and
Bar.pm simply loading Foo.pm.
-
The only issue left is to how to bootstrap Bar.xs. This is done
from Foo.xs:
-
MODULE = Cool::Foo PACKAGE = Cool::Foo
-
BOOT:
# boot the second XS file
boot_Cool__Bar(aTHX_ cv);
-
If you have more than two files, this is the place where you should
boot extra XS files from.
-
The following four files sum up all the details discussed so far.
-
Foo.pm:
-------
package Cool::Foo;
-
require DynaLoader;
-
our @ISA = qw(DynaLoader);
our $VERSION = '0.01';
bootstrap Cool::Foo $VERSION;
-
1;
-
Bar.pm:
-------
package Cool::Bar;
-
use Cool::Foo; # bootstraps Bar.xs
-
1;
-
Foo.xs:
-------
#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"
-
MODULE = Cool::Foo PACKAGE = Cool::Foo
-
BOOT:
# boot the second XS file
boot_Cool__Bar(aTHX_ cv);
-
MODULE = Cool::Foo PACKAGE = Cool::Foo PREFIX = cool_foo_
-
void
cool_foo_perl_rules()
-
CODE:
fprintf(stderr, "Cool::Foo says: Perl Rules\n");
-
Bar.xs:
-------
#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"
-
MODULE = Cool::Bar PACKAGE = Cool::Bar PREFIX = cool_bar_
-
void
cool_bar_perl_rules()
-
CODE:
fprintf(stderr, "Cool::Bar says: Perl Rules\n");
-
And of course a very basic test:
-
test.pl:
--------
use Test;
BEGIN { plan tests => 1 };
use Cool::Foo;
use Cool::Bar;
Cool::Foo::perl_rules();
Cool::Bar::perl_rules();
ok 1;
-
This tip has been brought to you by Nick Ing-Simmons and Stas Bekman.
If you have a question you'd like to see added to the FAQ (whether or
not you have the answer) please send it to makemaker@perl.org.
