From: E S <eero.saynatkari@...>
Date: 2005-01-09T02:55:34+09:00
Subject: Re: what's the Ruby way to do this?


> L�hett�j�: Florian Gross <flgr@ccan.de>
> Aihe: Re: what's the Ruby way to do this?
> 
> William James wrote:
> 
> > "If you have never worked with regular expressions before,
> > they probably look anything but regular".
> > 
> > How true that is!  I am not as familiar with Ruby-style
> > regular expressions as I would like to be, since I've done
> > much more programming in Awk, which has less powerful ones.
> > I see now that I could have made it shorter (and I wouldn't
> > be surprised if Florian Gross could make it "yet shorter"):
> > 
> > def snippet(thought)
> > thought.match(/(\S+(\s+|$)){0,10}/)[0]+($'>""?"...":"")
> > end
> 
> Let's try then:
> 
> def snippet(thought)
>    result = thought.clone
>    result[/^(?:\S*\s+){9}\S*(.+)$/, 1] = "..."
> ensure
>    return result
> end
> 
> def snippet(thought)
>    thought.sub(/^((?:\S*\s+){9}\S*)(.+)$/, '\1...')
> end
> 
> But actually I still prefer the solution I gave earlier. Regexps are 
> harder to understand than the equivalent code and gain you little in 
> this case. (Even if you know them, there's still some advanced trickery 
> involved in our pieces of code.)

Many things could be considered the 'Ruby Way', but none moreso than
messing with the standard library :) 

class String
  # snippet / Method
  # -- Shows the first N words of the String with a continuation.
  def snippet(words = 10, continuation = '...')
    ary = self.split[0...words]
    ary[words - 1] << continuation if ary[words]
    ary.join(' ')
  end
end

p "I just finished reading Dan Simmons' Iliad, it was very good.".snippet
# => I just finished reading Dan Simmons' Iliad, it was very...
p "I just finished reading Dan Simmons' Iliad, it was very good.".snippet(3)
# => I just finished...
p "I just finished reading Dan Simmons' Iliad, it was very good.".snippet(10, "...\n<a href="/articles/23">Read more...</a>")
# => I just finished reading Dan Simmons' Iliad, it was very...
     <a href="/articles/23">Read more...</a>

E