G'day harangzsolt33,

"Is there a website that explains what each builtin function does ..."

Yes: https://perldoc.perl.org/perl.

"... and how to use it with a little demo program that one can test?"

Most of the entries in perldoc have examples (or links to other manpages with examples).

If you're looking for specific tests, try https://github.com/Perl/perl5. You can pick a specific branch or tag. The default is "blead" but, let's say you wanted the latest stable release (at the time of writing), you'd pick the v5.36.1 tag and get https://github.com/Perl/perl5/tree/v5.36.1. From here you can select the "t" directory where you'll find all of tests: check the README and drill down into subdirectories for specific tests.

"I copied all the functions from perldoc ..."

Perhaps you need to be more specific. To me, that means you looked in https://perldoc.perl.org/functions; however, if you'd done that, you wouldn't be asking where to find function documentation.

There's also a Search function in the top-righthand corner of https://perldoc.perl.org/perl.

— Ken

In reply to Re: How to find Perl demo programs? by kcott
in thread How to find Perl demo programs? by harangzsolt33

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