Re: Why doesn't quantifier work with character classes?

I thought {8} will match exactly 8 characters, but looks like I am wrong!

You aren't wrong, it does match exactly 8 characters ... but if those 8 characters are at the start of a line containing more than 8 characters, it still matches exactly the first 8.

You need to anchor your regex: Ie. /^[ATGC]{8}$/. Now it will only match lines that contain exactly 8 characters.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.

"Science is about questioning the status quo. Questioning authority".

In the absence of evidence, opinion is indistinguishable from prejudice.

The start of some sanity?

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Re^2: Why doesn't quantifier work with character classes? by thezip (Vicar) on Aug 13, 2012 at 22:30 UTC
Please correct me if I am wrong (or if I misunderstood your statement), but there is nothing in OP's regex that restricts a match to the beginning of a line. Hence, the eight consecutive characters may appear anywhere on a line. Right? What can be asserted without proof can be dismissed without proof. - Christopher Hitchens, 1949-2011	[reply]
Re^3: Why doesn't quantifier work with character classes? by BrowserUk (Patriarch) on Aug 13, 2012 at 22:53 UTC
Hence, the eight consecutive characters may appear anywhere on a line. Right? Yes, but since the lines that match the character class in question contain only those characters; and a regex will always match as early as possible; that'll be at the beginning of the line in these cases. With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice. The start of some sanity?	[reply]
Re^3: Why doesn't quantifier work with character classes? by rnaeye (Friar) on Aug 13, 2012 at 22:34 UTC
Correct! "BrowserUk" and "thezip" 's suggestions solved the problem. Thanks.	[reply]


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