"Next time I'll just add a link to my script."

Be aware that some are averse to following off-site links, especially if they point to unknown sites.

What's your problem with using <readmore>? You could use <spoiler> if you think that better suits you. For what it's worth, I generally choose <spoiler> over <readmore> because it displays the hidden text in situ rather than via a "Read more ..." link which overwrites the current page unless I specify that it should be opened in a new tab (which then splits the thread across two tabs).

"... even if the warnings.pm file doesn't exist, warnings will be turned on."

No, that's wrong. Your script will not run. You'll get something like this:

Can't locate warnings.pm in @INC ...
BEGIN failed--compilation aborted ...
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