From: "Lorenzo E. Danielsson" <danielsson.lorenzo@...>
Date: 2008-08-15T02:09:53+09:00
Subject: Re: Idiom of removing a particular character from a String?

On Thu, 2008-08-14 at 23:52 +0900, Michael Libby wrote:
> On Thu, Aug 14, 2008 at 9:21 AM, Lorenzo E. Danielsson
> <danielsson.lorenzo@gmail.com> wrote:
> > Hi all,
> >
> > Is there any particular idiom for removing a particular character from a
> > string *by index* and returning the resulting string? The following
> > makes my old eyes sore:
> >
> > rem = str.clone
> > rem[i] = ""
> > rem
> >
> > as does this:
> >
> > rem = str.scan(/./)
> > rem.delete_at(i)
> > rem.to_s
> >
> > It seems there should be some more idiomatic way to do this, something
> > like str.annihilate_char_at_index_possibly_without_a_bang(i), read as
> > String#delete_at(i) and String#delete_at!(i). Of course these methods
> > don't exist, and "".methods doesn't turn up anything interesting. So
> > what is a *decent* way of performing this?
> 
> irb(main):022:0> rem = "foobar"
> => "foobar"
> irb(main):023:0> rem.slice!(3).chr
> => "b"
> irb(main):024:0> rem
> => "fooar"

The "problem" is that slice does not return the resulting string but
rather the sliced portion. This is of course not a problem in itself, it
is rather the expected behavior of slice. But, in my particular case
that *still* leads to:

str = "hello"
rem = str.clone
rem.slice!(2)
rem # => "helo"

Whereas I would have wanted:

str = "hello"
rem = str.slice_and_return_everything_but_the_sliced_part(2) 

This is partly a matter of laziness on my part, that I prefer to type
two lines instead of four. But, it is also a matter that it kind of
breaks the POLS, at least for me. I have grown accustomed to being able
to perform:

result = original.some_method(args)

and have the result be some mutilated form of original, with original
being left intact. So when String#delete_at(index) doesn't work, it
feels like it *should* have worked..

Anyways, nothing worth losing sleep over..

> 
> -Michael
>