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- Subject: Re: Can LPeg parse PNG?
- From: "Soni L." <fakedme@...>
- Date: Sat, 10 Dec 2016 00:23:40 -0200
On 09/12/16 11:46 PM, Duncan Cross wrote:
On Sat, Dec 10, 2016 at 12:10 AM, Soni L. <email@example.com> wrote:
I was told PNG is a regular language, in the sense that you can validate any
PNG chunk with a VERY VERY VERY LONG regex.
Including the 32-bit CRC at the end of the chunk? That's got to be a
hell of a regex.
Only 256^2^2^32 alternations or something. While not practical, it is,
mathematically speaking, possible. However, that's just for the raw
chunks - regex wouldn't work for chunk contents or compression, which's
why this is an LPeg challenge, not a regex challenge.
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