From: Robert Klemme <shortcutter@...>
Date: 2007-08-03T22:07:07+09:00
Subject: Re: Fast implementation of XML escape

2007/8/3, Bob Hutchison <hutch@recursive.ca>:
> Hi Robert,
>
> Thanks for the response.
>
>
> On 3-Aug-07, at 8:47 AM, Robert Klemme wrote:
> >
> > You are on the right track. There is just one thing to improve: get
> > rid of "case":
> >
> > class Converter
> >   MAP = {
> >     "&" => "&amp;",
> > # ...
> >   }
> >
> >   def self.convert(s)
> >     s.gsub(/[&<>'"]/) do |m|
> >       MAP[m] || "ERROR"
> >     end
> >   end
> > end
>
>
> My version3 was:
>
> @@convert = {
>    '&' => '&amp;',
>    '<' => '&lt;',
>    '>' => '&gt;',
>    "'" => '&apos;',
>    '"' => '&quot;'
> }
>
> def version3(input)
>    # all kinds of other processing of input simulated by the input.dup
>    result = input.dup
>
>    result.gsub!(/[&<>'"]/) do | match |
>      @@convert[match]
>    end
>
>    return result
> end
>
> which is pretty much what you suggested, but it takes 29.71 seconds
> (rather than 8.74 seconds).

The overhead of the block form is significant.  It probably pays off
when you have longer strings.   That depends.

Kind regards

robert