BUT what's really confusing me is that pos($str) is empty afterwards!

pos is updated by every search. It is either advanced on success, or reset on a match failure (unless you use /c). If it didn't reset, a match somewhere in the program could affect an unrelated match elsewhere in the program.

produces [...] and an endless loop!

Position zero is the start of the string. It doesn't surprise me that it thinks it hasn't matched yet.

It lets you do something silly like /.\G/ assuming you know what you are doing. Expect problems if you break that trust by trying to match the character before the start of the string and nothing else.

In reply to Re: [bugs?] perldoc perlre, \G and pos() by ikegami
in thread [bugs?] perldoc perlre, \G and pos() by LanX

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