search() vs ignorecase vs smartcase about vim

[k-takata]

Perl's regex can turn on/off ignore case only a part of the pattern: (?i:aaa)|BBB.
However, Vim doesn't support such pattern.

[chrisbra]

Well, smartcase means, if you have a pattern with at least one upper case character, the search becomes case sensitive. And that's what's happening here.

[097115]

Oh, the whole pattern, not just that uppercased part... I see, thanks, Christian!

(On a side note, and if I want to match here aaa, AAA and BBB, I simply have list everything in the pattern, there's no some other smart way? )

[chrisbra]

Not sure what you want to match. You could use ^\w\{3\}$