```{index} single: hash_value; Hash::Util function ``` ```{index} single: Hash::Util::hash_value; Perl function ``` # hash_value Return the integer hash value of a string under the current (or a supplied) seed. ## Synopsis my $h = hash_value($string); my $h = hash_value($string, $seed); With one argument, hashes `$string` with the interpreter's per-process seed — the same seed reported by `hash_seed`. With a second argument, hashes it with `$seed` instead, letting you compute what the hash value *would* be under a different seed. The custom seed must be at least as long as `hash_seed` produces; a shorter `$seed` croaks with `seed len must be at least N long only got M bytes`. The one-argument value is stable for the lifetime of a single interpreter and unstable across runs, Perl versions, build options, and architectures. Do not persist it. Like `hash_seed`, the result is sensitive information that can be used to engineer collisions. Treat it accordingly.