Re^2: Globs and globals

This advice is factually incorrect.

GLOB is a glob, and local doesen't help here ( besides providing false sense of security )

my $socket=\*S1;
print "Orig:",$socket,"\n";
{
local(*S1, *S2);
my $s=\*S1;
print "Local: ",$s,"\n";
}
[download]

Orig:GLOB(0x8160be4)
Local: GLOB(0x8160be4)

Comment on Re^2: Globs and globals Download Code

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Re^3: Globs and globals by BrentDax (Hermit) on Jan 25, 2005 at 18:40 UTC
Odd--you're right, though I can't figure out why. The docs seem to say that you get a new glob when you localize: The construct `local name;` creates a whole new symbol table entry for the glob "name" in the current package. That means that all variables in its glob slot ($name, @name, %name, &name, and the "name" filehandle) are dynamically reset. In any case, the following does* work correctly: `open(S1, "/dev/null"); $a=S1{IO}; { local(S1); open(S1, "/dev/null"); $b=*S1{IO}; } print "$a $b\n";` [download] IO::Handle=IO(0x101536f8) IO::Handle=IO(0x1013cdec) =cut --Brent Dax There is no sig.	[reply] [d/l] [select]
Re^4: Globs and globals by Eyck (Priest) on Jan 26, 2005 at 06:34 UTC
Interesting, your code works, although I would expect it not to. I haven't seen this excerpt in documentation about local and globs so it's a bit of surprise for me, thanks. There must be something about dual nature of globs - whatever experiment you devise it proves your theory, even if it contradicts other experiments.	[reply]
Re^5: Globs and globals by BrentDax (Hermit) on Jan 26, 2005 at 10:29 UTC
I think it may be that `local glob` localizes the contents* of `*glob`, not the glob itself. The docs could be read to support that. Or maybe it's just that the superposition-like nature of globs means that their behavior is governed by the Heisenburg Uncertainty Principle. Yeah, that's it... =cut --Brent Dax There is no sig.	[reply] [d/l] [select]