From: "Lorenzo E. Danielsson" <danielsson.lorenzo@...>
Date: 2008-08-15T01:59:51+09:00
Subject: Re: Idiom of removing a particular character from a String?

On Thu, 2008-08-14 at 23:40 +0900, Gregory Seidman wrote:
> On Thu, Aug 14, 2008 at 11:21:10PM +0900, Lorenzo E. Danielsson wrote:
> > 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? 
> 
> str[index..index] = ""

So:
str = "hello"
rem = str.clone
rem[2,1] = ""  # => "helo"
rem

Sorry, but that doesn't look any cleaner than my solution. I was looking
for something like:

class String
  def delete_at(i)
    str = self.clone
    str[i] = ""
  end
end

str = "hello"
rem = str.delete_at(2) # => "helo"

That is, original string does not get tampered with. Resulting string is
original string minus exactly one character, at the specified index.

The above works, but I was hoping to avoid that by using some neat
idiom. This is not really a problem, but 99.x % of the time, Ruby does
things in a way that are so cool that I tend to get lazy and expect it
to always behave that way. The few times it doesn't, it comes as a
shock.

> 
> > Lorenzo
> --Greg
> 
>