This Week on perl5-porters (16-22 December 2002)
This week, in spite of the approaching holidays, the Perl 5 porters
mailing list wasn't completely silent. Read about version objects,
various warnings, operator precedence design, and a birthday.
Version object updates
The (apparently) never-tired John Peacock pulled another improvement of
his version object patches, that should now, as he says, satisfy
everyone. Basically we have now (in version.pm v0.25, found on CPAN)
version->new(1.10) < version->new(1.2) # 1.100 < 1.200
version->new("1.10") > version->new("1.2") # 1.010 > 1.002
The integration of this into bleadperl will wait until next year, if a
full consensus is reached -- see the thread for the porters' comments.
http://groups.google.com/groups?threadm=3DFF94D7.6020605%40rowman.com
New warning discussed
Benjamin Goldberg proposed to introduce a new warning, aimed at warning
programmers against using a $DIGIT variable when the previous regular
expression didn't match, as in :
$str =~ /(something)/; print $1;
In fact he proposes the warning to be triggerred whenever a regular
expression match is used in void context. Among the points discussed
were: should this be a run-time or a compile-time warning ? Should it be
limited to failing matches ? Should it warn when the $DIGIT variables
aren't used ? What about regular expression with side-effects ?
http://groups.google.com/groups?threadm=3E001681.BC9B0946%40earthlink.net
A bit of language design
Larry Wall commented about the recently modified parsing of the "? :"
ternary operator, proposed by Stephen McCamant one month ago. Current
perls reject "$cond ? $a and $b : $c;" as a syntax error, and Stephen
provided a patch to accept this. However, Larry notes that with this
patch,
$cond ? $a and $b : $c and $d;
would be equivalent to
($cond ? $a and $b : $c) and $d;
which doesn't look like the Right Thing.
http://groups.google.com/groups?threadm=200212200035.gBK0ZRm29309%40crypt.compulink.co.uk
Perl birthday present
Perl is 15 years old ! To commemorate this event, perl 1.0.15, the
latest maintenance release of Perl 1, was released by Michael G Schwern.
http://groups.google.com/groups?threadm=20021218235532.GA852%40blackrider.schwern.org
In brief
Michael also released an alpha version (6.06_01) of MakeMaker, and asked
for testers, notably on non-Unix platforms, and for complex modules.
Some problems were reported on Windows.
Jos Boumans remarks that on Windows, both 'Foo/Bar.pm' and
'Foo\\Bar.pm' could be set as keys in the %INC hash. This behavior
could cause problems, notably with IPC::Run. (Bug #19213)
Steve Noynaert reported a couple of strange build problems on AIX, one
of them involving breakage of the glob() function. Nicholas Clark
suggested that his system (libraries and/or compiler versions) could be
blamed for this.
H. Merijn Brand suggested that "perl -v" should report the patchlevel on
developement build (as "perl -V" does).
Dave Mitchell continues to patch the lexical engine, first by proposing
to remove the useless SvPADBUSY flag, then by introducing a new flag
SvPADSTALE, "set on a lexical in a pad which has gone out of scope".
Paul Marquess asked for a good generic way to catch C++ exceptions in
XSUB code and to pass them back to Perl code.
Jeff Sumler notes that the infamous warning "Use of uninitialized value"
would be better written "Use of undefined value", as one could
initialize a value to undef on purpose.
Clinton Pierce reported bug #18917, about system() executing external
commands twice on Win32 in some cases, when its exit status is non null.
About this summary
This summary brought to you by Rafael Garcia-Suarez, from holidays on
the French Riviera, where he insanely brought his new laptop. Read it on
http://use.perl.org/ and/or via a mailing list, which subscription
address is [EMAIL PROTECTED] Comments and corrections
are, as always, welcome.
