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Postings from June 2003
In article <20030603155453.4004_58e.rgarciasuarez@_ree._r>,
Rafael Garcia-Suarez <rgarciasuarez@free.fr> writes:
> Yes. Good catch. Setting /m on a match or on a substitution is
> equivalent to setting the global special variable $* to 1 (locally).
> Thus, it will influence the behaviour of all regexps that haven't /m or
> /s set in that scope.
That makes things even weirder:
perl -wle '
sub fun {
$a = shift;
print "\$* is undef" if !defined($*);
local $* = undef;
print "fun(<$a>)";
print "unexpectdly matched $& at position @-" if /^de/
}
$_ = "ab\nde";
s/^([\w\W]*)/fun("$1")/em'
gives:
Use of $* is deprecated at -e line 4.
$* is undef
Use of uninitialized value in scalar assignment at -e line 5.
fun(<ab
de>)
So setting $* to undef (or 0) indeed solves it.
However, the test before the local shows that $* actually
already was undef !. But removing the local makes it fail again.
Urgh !
>
> The interaction with $*, and the fact that $* can have remote effects,
> makes this bug difficult to solve.
>
> A first step would be to make $* lexically scoped (a compile-time hint,
> à la $[). Or to get rid of it.
Making $* lexically scoped probably already breaks pograms that still
depend on it. So kill it, I'd say. It has been documented as deprecated
for a long time, and gives a deprecation warning in actual code.
Now it's also clear it causes bugs in real code.
(nope, this wasn't a golf thing :-) )
--
seen in rec.arts.sf.written: "Perl Harbor" was the C-port for Awk-land, NZ
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