in reply to Re^2: conditional expression testing
in thread conditional expression testing

m#^(hana)(bbs)?(?(1)\2\1|\1)$#;

is the same as

m#^(hana)(bbs)?\2\1$#;

since (?(1)...) is always true. And since you don't use the captures, that can be be simplified to

m#^hana(?:bbsbbs)?hana$#;