What does x<0> mean?

It means "Don't do anything", or rather: "ignore that x". Just as x{0} does in Perl 5.

Don't accept an x here?

No. That's <!before x> in Perl 6. Or (?!x) in Perl 5.

Which is not the same as "Accept something that isn't an x". That would be <-[x]> in Perl 6 and [^x] in Perl 5.

In reply to Re: Re: Re: Do nothing? or Do something important in a very obscure way? by TheDamian
in thread Do nothing? or Do something important in a very obscure way? by BrowserUk

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