From: Trans <transfire@...>
Date: 2009-08-24T21:45:12+09:00
Subject: Re: 1.8.7 String#lines keeps new-line chars (say it ain't so in 1.9)



On Aug 24, 4:50 am, Brian Candler <b.cand...@pobox.com> wrote:
> Thomas Sawyer wrote:
> > On Aug 23, 3:32 am, Brian Candler <b.cand...@pobox.com> wrote:
>
> >> Perhaps most importantly of all, if the newlines were stripped, there
> >> would be loss of data and it would be impossible to reconstruct the
> >> original file exactly from the members of the lines array (e.g.
> >> lines.join), as your example shows nicely.
>
> > How is there loss of data, when you know what was removed? Just join
> > ("\n").
>
> "Loss of data" means "you don't get back exactly what you started with".
> Taking your example, I believe that you want both "A\nB\nC" and
> "A\nB\nC\n" to result in lines ["A","B","C"], so this operation is not
> reversible.
>
> Or did you want "A\nB\nC\n" to result in ["A","B","C",""] ?  That would
> surprise me more. Most inputs have terminating newlines on the final
> line.

Granting that prefect reversibility is a requirement here, then yes
the later makes sense. I do not think it surprising.

To me returning the newline code with #lines would be like returning
the spaces for a method #words. Eg.

  "show it\nto me".words => ["show ", "it\n", "to ", "me "]

I think the broader issue here is the question of whether or not
String is intended for use by code-point (ie. low-level character)
manipulators, or for higher-level human-oriented textual manipulation.
I always thought StringIO was for the former case. But now I am seeing
Ruby's String is some sort of hodge-podge mixture of the two.




T.