From: William James <w_a_x_man@...>
Date: 2006-12-03T13:25:09+09:00
Subject: Re: comma separating output from array.to_s

Gregory Brown wrote:
> On 12/2/06, William James <w_a_x_man@yahoo.com> wrote:
> > Gregory Brown wrote:
> > > On 12/2/06, jansenh <henning.jansen@gmail.com> wrote:
> > > > hi comp.lang.ruby
> > > >
> > > > what is the ruby-way of comma separating the output from array.to_s?
> > >
> > > some_array.join(",")
> > >
> > > but if you are thinking of doing CSV output, you should not use a
> > > naive approach like this, since it will likely produce malformed CSV
> > > when dealing with quoted text.
> >
> >

> >  puts [22,'He said, "No!"'].map{|x| x=x.to_s
> >    x =~ /["\n]/ ? '"' + x.gsub(/"/,'""') + '"' : x }.join(',')
> > 22,"He said, ""No!"""
>
> Yeah, now deal with edge cases, and try to run that on 100k rows :)

It's easy to handle all cases since CSV is a simple format;
no pompous prolixity is needed:

puts ['x',' y ','He said, "No!"'].map{|x| x=x.to_s
  x =~ /["\n]|^\s|\s$/ ? '"' + x.gsub(/"/,'""') + '"' : x }.join(',')
x," y ","He said, ""No!"""

If that won't handle 100k rows, then fasterCsv probably won't either.