Corion is correct. If, for some reason, you don't want to define a sub that does this, you can use an anonymous sub the same way.

my $parameter = qq{param at declaration\n};
my $print_ref = sub { my ($p) = @_; sub { print $p } }->( $parameter )
+;

$print_ref->();

$parameter = qq{param after declaration\n};

$print_ref->();
__END__
param at declaration
param at declaration
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I wouldn't recommend this for anything more complicated than a single line, however. I wouldn't want to read to the end of a block of code to find "->(...)" dangling off of it.