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# values

Perl 5 version 18.2 documentation
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# values

Perl functions A-Z | Perl functions by category | The 'perlfunc' manpage

- values HASH

- values ARRAY
- values EXPR

  In list context, returns a list consisting of all the values of the named hash. In Perl 5.12 or later only, will also return a list of the values of an array; prior to that release, attempting to use an array argument will produce a syntax error. In scalar context, returns the number of values.

  Hash entries are returned in an apparently random order. The actual random order is specific to a given hash; the exact same series of operations on two hashes may result in a different order for each hash. Any insertion into the hash may change the order, as will any deletion, with the exception that the most recent key returned by `each` or `keys` may be deleted without changing the order. So long as a given hash is unmodified you may rely on `keys`, `values` and `each` to repeatedly return the same order as each other. See Algorithmic Complexity Attacks in perlsec for details on why hash order is randomized. Aside from the guarantees provided here the exact details of Perl's hash algorithm and the hash traversal order are subject to change in any release of Perl.

  As a side effect, calling values() resets the HASH or ARRAY's internal iterator, see each. (In particular, calling values() in void context resets the iterator with no other overhead. Apart from resetting the iterator, `values @array` in list context is the same as plain `@array` . (We recommend that you use void context `keys @array` for this, but reasoned that taking `values @array` out would require more documentation than leaving it in.)

  Note that the values are not copied, which means modifying them will modify the contents of the hash:

          for (values %hash)      { s/foo/bar/g }  # modifies %hash values    for (@hash{keys %hash}) { s/foo/bar/g }  # same

  Starting with Perl 5.14, `values` can take a scalar EXPR, which must hold a reference to an unblessed hash or array. The argument will be dereferenced automatically. This aspect of `values` is considered highly experimental. The exact behaviour may change in a future version of Perl.

          for (values $hashref) { ... }    for (values $obj->get_arrayref) { ... }

  To avoid confusing would-be users of your code who are running earlier versions of Perl with mysterious syntax errors, put this sort of thing at the top of your file to signal that your code will work only on Perls of a recent vintage:

          use 5.012;	# so keys/values/each work on arrays    use 5.014;	# so keys/values/each work on scalars (experimental)

  See also `keys`, `each`, and `sort`.