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?

In reply to Re: Why doesn't quantifier work with character classes? by BrowserUk
in thread Why doesn't quantifier work with character classes? by rnaeye

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