Yes, I was thinking as I wrote my reply that it would make more sense to break it as:

  /( (?: a+ | (?=c) ) )/x

[download]

But I didn't want to introduce unnecessary complications for the OP, and I wasn't entirely sure there was no deep reason I was missing as to why the docs show /a*/ rather than /a+/ for this.

Hugo

In reply to Re^3: ZERO_LENGTH match by hv
in thread ZERO_LENGTH match by sh1tn

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