Copy a string: Difference between revisions

To copy a string, just use ordinary assignment:

<perl>my $original = 'Hello.';

my $new = $original;

$new = 'Goodbye.';

print $original, "\n"; # prints "Hello."</perl>

To create a reference to an existing string, so that modifying the referent changes the original string, use a backslash:

<perl>my $ref = \$original;

$$ref = 'Goodbye.';

print $original, "\n"; # prints "Goodbye."</perl>

If you want a new name for the same string, so that you can modify it without dereferencing a reference, assign a reference to a typeglob:

<perl>our $alias;

local *alias = \$original;

$alias = 'Good evening.';

print $original, "\n"; # prints "Good evening."</perl>

Note that <code>our $alias</code>, though in most cases a no-op, is necessary under stricture. Beware that <code>local</code> binds dynamically, so any subroutines called in this scope will see (and possibly modify!) the value of <code>$alias</code> assigned here.