regex issue in javascript

Question

"foo = '@test.bar';\nfooa = @test.darn;".match(/@([a-z][a-z\.-_]*)/igm)

Why does this match

["@test.bar", "@test.darn;"]

rather than just

["@test.bar", "@test.darn"]

?

Answer 1

In character classes, some letters have special meanings. The dot for example has none and does not need to be escaped. The minus in contrast defines a range of characters, and if you mean literally minus you need to escape it or put it in the end/beginning of the character class. Your range from . to _ actually includes ./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_. You may want to use [a-z.\-_] or [a-z._-] instead.