I was about to comment (sarcastically) on Removing underscores. when I got confused by somehting, so I am here seeking knowledge from a monk wiser than I. I tried this:

perl -e 'my $str = "This_is_a_song_.mp3"; substr($str, 14, 1, ''); pri
+nt $str."\n";'

[download]

and got:

This_is_a_song_.mp3

[download]

I would have expected substr to remove the last underscore (the character at offset 14). However it appears that because my replacement had a length of zero, perl acted as though I hadn't given it a replacement. Does the "REPLACEMENT" argument to substr need to have length in order to be considered valid?

substr

Update: My ignorance has been discovered. Thank you all for sharing your knowledge

They say that time changes things, but you actually have to change them yourself.

—Andy Warhol

In reply to Using substr to remove characters by JediWizard

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