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+package Env;
+
+=head1 NAME
+
+Env - Perl module that imports environment variables
+
+=head1 DESCRIPTION
+
+Perl maintains environment variables in a pseudo-associative-array
+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 $PATH;
+
+=head1 AUTHOR
+
+Chip Salzenberg <chip@fin.uucp>
+
+=cut
+
+sub import {
+ my ($callpack) = caller(0);
+ my $pack = shift;
+ my @vars = @_ ? @_ : keys(%ENV);
+
+ foreach (@vars) {
+ tie ${"${callpack}::$_"}, Env, $_ if /^[A-Za-z_]\w*$/;
+ }
+}
+
+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;