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+package Env;
+
+=head1 NAME
+
+Env - perl module that imports environment variables
+
+=head1 SYNOPSIS
+
+ use Env;
+ use Env qw(PATH HOME TERM);
+
+=head1 DESCRIPTION
+
+Perl maintains environment variables in a pseudo-hash named %ENV. For
+when this access method is inconvenient, the Perl module C<Env> allows
+environment variables to be treated as simple variables.
+
+The Env::import() function ties environment variables with suitable
+names to global Perl variables with the same names. By default it
+does so with all existing environment variables (C<keys %ENV>). If
+the import function receives arguments, it takes them to be a list of
+environment variables to tie; it's okay if they don't yet exist.
+
+After an environment variable is tied, merely use it like a normal variable.
+You may access its value
+
+ @path = split(/:/, $PATH);
+
+or modify it
+
+ $PATH .= ":.";
+
+however you'd like.
+To remove a tied environment variable from
+the environment, assign it the undefined value
+
+ undef $PATH;
+
+=head1 AUTHOR
+
+Chip Salzenberg E<lt>F<chip@fin.uucp>E<gt>
+
+=cut
+
+sub import {
+ my ($callpack) = caller(0);
+ my $pack = shift;
+ my @vars = grep /^[A-Za-z_]\w*$/, (@_ ? @_ : keys(%ENV));
+ return unless @vars;
+
+ eval "package $callpack; use vars qw("
+ . join(' ', map { '$'.$_ } @vars) . ")";
+ die $@ if $@;
+ foreach (@vars) {
+ tie ${"${callpack}::$_"}, Env, $_;
+ }
+}
+
+sub TIESCALAR {
+ bless \($_[1]);
+}
+
+sub FETCH {
+ my ($self) = @_;
+ $ENV{$$self};
+}
+
+sub STORE {
+ my ($self, $value) = @_;
+ if (defined($value)) {
+ $ENV{$$self} = $value;
+ } else {
+ delete $ENV{$$self};
+ }
+}
+
+1;