From: Ryan Davis <ryand-ruby@...>
Date: 2010-10-05T08:09:24+09:00
Subject: Re: How to suppress display of specific code in irb??


On Oct 4, 2010, at 14:55 , Don Norcott wrote:

> Thanks these all did the trick. I especially like the toggle.
> 
> However even after finding the solution I still could not find where any 
> of this is documented.

Sure it is. It is documented everywhere. From the pickaxe:

"irb will display the value of each expression as you complete it. For instance: [...irb examples...]"

> I would like to see an explanation of "string"; null.

nil, not null.

What more explanation do you want to see, and where? If you have a lot of output from an expression, you augment that expression so that it isn't the final result. 

> I find that adding only a semicolon (no nil)does the trick
> doc = Nokogiri::HTML(open(url)); # produces no display

No, it doesn't. Look at my prompts:

> 501 % irb
> >> "blah"
> => "blah"
> >> "blah";
> ?> 

You've told ruby (irb actually) that there is more coming. That's all.

> Can you point me to some documentation than may explain the solutions, 
> so I know where to look next time.

Again. Everywhere. The pickaxe has an entire chapter on the subject.