Buehler, Bob wrote:
local(*in);
Does this indicate that you want to make all variables that begin with
$in private?
No.
Perl has two kinds of scoping: lexical and dynamic. Lexical scoping
means the name only has meaning with the block, or if outside any block,
within the file. Dynamic scoping means within the block and in any
subroutine called in the block. The keyword local is used to set dynamic
scoping. For example:
open FILE, "< myfile.txt" or die 'cannot open myfile.txt: $!\n";
my $contents = '';
{
local $/; # set $/ to undef
$contents = <FILE>; # slurps the entire file, \n's included
}
# End of block, $/ reset to whatever it was before.
close FILE;
Here dynamic scoping is used as a stack to preserve $/ while the file is
slurped.
In 'local(*in);' the phrase '*in' is a typeglob. It means every
identifier 'in'. This includes $in, @in, %in, sub in, and file handler
'in'. Localizing 'in' would set all of them to undef.
To privatize a variable, use 'my'. Try this example:
#!/usr/bin/perl
use strict;
use warnings;
my $var = 'This is a test.';
print "$var\n";
{
my $var = 'foobar';
print "$var\n";
}
print "$var\n";
__END__
'my' privatizes $var to the file and to the block while inside the
block. You would have to use 'our' (in both files) to get a global
variable shared between files.
You will have to experiment with 'my', 'our', and 'local' to see exactly
what they do; an full explanation is beyond a simple e-mail.
--
Just my 0.00000002 million dollars worth,
--- Shawn
"Probability is now one. Any problems that are left are your own."
SS Heart of Gold, _The Hitchhiker's Guide to the Galaxy_
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