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8.46 Env

Lets your program treat environment variables as simple variables instead of having to access them from the %ENV pseudo-hash where they are kept.

use Env;

use Env qw(
var1
 
var2
 ...);
Internally, Env uses an import function that ties suitably named environment variables to global Perl variables with the same names. By default, it ties all variables yielded by keys %ENV . A "suitable" environment has a name that begins with an alphabetic character and contains only alphanumeric characters or underscores.

When use Env is invoked with arguments, the arguments are interpreted as a list of environment variables to tie , but the variables don't have to exist yet. After a variable has been tied, you can use it like a normal variable, accessing or changing its value.

You untie a variable by setting its value to undef .











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