From: pharrington <xenogenesis@...>
Date: 2010-01-02T04:30:04+09:00
Subject: Re: Delete elements in array, break, and keep changes?

On Jan 1, 2:19 pm, pharrington <xenogene...@gmail.com> wrote:
> On Jan 1, 2:18 pm, pharrington <xenogene...@gmail.com> wrote:
>
>
>
>
>
> > On Jan 1, 11:45 am, Joe Buck <semle2...@hotmail.com> wrote:
>
> > > Ehsan,
>
> > > Thanks for the help. Unfortunately I don't think that will work as it
> > > removes the first element in the array.
>
> > > What I need is an Array::delete_if or Array::reject! call that allows me
> > > to break from the block while still removing elements.
>
> > > My solution is to use a second array to keep the indices of all removed
> > > elements. I can then iterate through the second array after the first
> > > loop and remove the elements. I'm guessing reject! and delete_if do this
> > > as well. It could be more efficient but it works.
>
> > > Thanks!
> > > --
> > > Posted viahttp://www.ruby-forum.com/.
>
> > Without knowing the point of what you're trying to do, this sounds
> > like what you have in mind:
>
> > array = [] # or whatev
> > process_array = true
> > array.reject!(x) do
> >   if process_array
> >     conditional_code_for x
> >   else
> >     false
> > end
>
> Also, is the reject! really the bottleneck in your app? We obviously
> don't want to intentionally write sub-optimal code, but do not
> optimize what's not slowing you down.

wow array.reject! do |x| i don't know basic ruby syntax today...

Or if you really want to avoid even iterating over each element:

original_array = []
new_array = []

original_array.each {|x| new_array << x unless conditional_code_for
(x)}

But again, what precisely are you doing? Is the deletion code really
your bottleneck? And if it is, I'm almost certain that using a more
appropriate structure than an array would be the way to go.