Zero-width positive "look-behind"?

“tttttattttt”.match(/ttt(?=a)/) # http://rubular.com/r/21Zo6JP09f
=> [“ttt”]
“tttttattttt”.match(/(?=a)ttt/) # http://rubular.com/r/d1VSUwwZUu
=> nil

Why? And how can I get this effect?

On 04/09/2010 10:40 AM, Nathan wrote:

“tttttattttt”.match(/ttt(?=a)/) # http://rubular.com/r/21Zo6JP09f
=> [“ttt”]
“tttttattttt”.match(/(?=a)ttt/) # http://rubular.com/r/d1VSUwwZUu
=> nil

Why? And how can I get this effect?

It seems you have just demonstrated how to get the effect you described.

For more info:

http://www.geocities.jp/kosako3/oniguruma/doc/RE.txt

Note: you need Ruby 1.9.

Kind regards

robert

Ah (?<=a)ttt is what I was after. Thanks for the link.

This forum is not affiliated to the Ruby language, Ruby on Rails framework, nor any Ruby applications discussed here.

| Privacy Policy | Terms of Service | Remote Ruby Jobs