Re^5: better (faster) way of writing regexp

Well, it's not that hard to write a perl one-liner and see if any of them matches \d, is it? It takes far less keystrokes than your question.

Having said that, as far as I can determine, 一 (CJK UNIFIED IDEOGRAPH-4E00) and 十 (CJK UNIFIED IDEOGRAPH-5341) are classified as a letter (\p{Lo}), with numerical values 1 and 10.

As I said before, to be considered a digit, you'll have to be a number between 0 and 9 (inclusive), and not part of a greater set. I do not believe 10 to be between 0 and 9.

Comment on Re^5: better (faster) way of writing regexp

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Re^6: better (faster) way of writing regexp by rovf (Priest) on Dec 02, 2009 at 16:57 UTC
Well, it's not that hard to write a perl one-liner and see if any of them matches \d, is it? Actually it is... From the links pointed out in Re^3: better (faster) way of writing regexp, I concluded that the exact interpretation of \d in Perl is still under discussion, and at least not implemented yet in Perl 5.8 (which is running here); and, I have not found an easy way to use Unicode on the Command Line in Windows 2000. As I said before, to be considered a digit, you'll have to be a number between 0 and 9 ... which would apply of 'ichi' (1), but, as you point out, certainly not for 'jue' (10). UPDATE: My comment regarding windows command line was silly. I can always represent Unicode characters by `\x(...)`, so, yes, you are right, it would have been easy to have written a short perl program to test it! -- Ronald Fischer <ynnor@mm.st>	[reply] [d/l] [select]
Re^7: better (faster) way of writing regexp by JavaFan (Canon) on Dec 02, 2009 at 17:49 UTC
I concluded that the exact interpretation of \d in Perl is still under discussion, and at least not implemented yet in Perl 5.8 (which is running here); \d has been implemented for a long time. Probably it was already in Perl 1.0.0. The meaning of `\d` may change, but I don't think consensus has been reached on the change (some people want \d to match `[0-9]`, but Larry has said Perl5 should not, which means that due to Rule 1, `\d` is likely to continue matching all Unicode digits). Considering that Jesse has declared a feature freeze for 5.12, the earliest Perl where `\d` may no longer match all Unicode digits will 5.14, but then only if Rule 1 can be revoked (using Rule 2, I presume). As I said before, to be considered a digit, you'll have to be a number between 0 and 9 ... which would apply of 'ichi' (1) I won't deny that. But please read the part of the sentence that follows "0 and 9". I didn't intent that part to be optional. The Chinese numbering system has symbols for 0 .. 10, 100, 1000, and other powers of 10. As such, they ain't digits. Now, you want to argue that 一 should match /\pN/, but that's something you would have to take up with the Unicode Consortium - Perl just follows their definition.	[reply] [d/l] [select]