Sherm Pendley dot-app.org> wrote:

Yup true.

This is an excerpt from the latest version perlfaq4.pod, which
comes with the standard Perl distribution. These postings aim to
reduce the number of repeated questions as well as allow the community
to review and update the answers. The latest version of the complete
perlfaq is at http://faq.perl.org .

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4.58: How can I know how many entries are in a hash?

If you mean how many keys, then all you have to do is use the keys()
function in a scalar context:

$num_keys = keys %%hash;

The keys() function also resets the iterator, which means that you may
see strange results if you use this between uses of other hash operators
such as each().

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Sherm Pendley dot-app.org> wrote:

[..]

Uhm, that depends. There is no problem with sending HTML ("AJAH") if
that's all you need.

Paul Lalli wrote:

This is an excerpt from the latest version perlfaq4.pod, which
comes with the standard Perl distribution. These postings aim to
reduce the number of repeated questions as well as allow the community
to review and update the answers. The latest version of the complete
perlfaq is at http://faq.perl.org .

--------------------------------------------------------------------

4.69: How can I use a reference as a hash key?

(contributed by brian d foy)

Hash keys are strings, so you can't really use a reference as the key.
When you try to do that, perl turns the reference into its stringified
form (for instance, "HASH(0xDEADBEEF)"). From there you can't get back
the reference from the stringified form, at least without doing some
extra work on your own. Also remember that hash keys must be unique, but
two different variables can store the same reference (and those
variables can change later).

The "Tie::RefHash" module, which is distributed with perl, might be what
you want. It handles that extra work.

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Outline
Before posting to comp.lang.perl.misc
Must
- Check the Perl Frequently Asked Questions (FAQ)
- Check the other standard Perl docs (*.pod)
Really Really Should
- Lurk for a while before posting
- Search a Usenet archive
If You Like
- Check Other Resources
Posting to comp.lang.perl.misc
Is there a better place to ask your question?
- Question should be about Perl, not about the application area
How to participate (post) in the clpmisc community
- Carefully choose the contents of your Subject header
- Use an effective followup style
- Speak Perl rather than English, when possible
- Ask perl to help you
- Do not re-type Perl code
- Provide enough information ...

This is an excerpt from the latest version perlfaq4.pod, which
comes with the standard Perl distribution. These postings aim to
reduce the number of repeated questions as well as allow the community
to review and update the answers. The latest version of the complete
perlfaq is at http://faq.perl.org .

--------------------------------------------------------------------

4.50: How do I select a random element from an array?

Use the "rand()" function (see "rand" in perlfunc):

$index = rand @array;
$element = $array[$index];

Or, simply:

my $element = $array[ rand @array ];

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