From: Robert Klemme <shortcutter@...>
Date: 2008-08-20T14:21:30+09:00
Subject: Re: Cut a string if length > n

On 19.08.2008 22:33, Rob Biedenharn wrote:
> On Aug 19, 2008, at 4:08 PM, Pål Bergström wrote:
> 
>> This seems to do the trick. Will it always work?
>>
>> lastspace = message.message[0..70].rindex(" ")
>> puts message.message[0..lastspace.to_i]
> 
> 
> You likely want an exclusive range unless you want the space at the end.
> 
> 	message.message[0...lastspace.to_i]
> 
> What if there's no space?  Then perhaps:
> 
> 	message.message[0..(lastspace || -1).to_i]
> 
> Of course, that puts you back in the position of getting the full  
> string rather than some truncated version with no more than your  
> desired number of characters.

Pal, it seems we haven't seen the complete specification of what you 
want to do.  It seems that not only length is a condition but also 
positions of spaces.

I get the feeling that a solution using regular expressions might be 
more efficient and also easier in your case.  Maybe any of

str.sub! %r{\A(.{50}).*\z}, '\\1'
str.sub! %r{\A(.{1,50})(?: .*)?\z}, '\\1'
str.sub! %r{\s\S*\z}, ''

Depends on your string contents of course.

Kind regards

	robert