From: "Hal E. Fulton" <hal9000@...>
Date: 2003-02-27T05:39:44+09:00
Subject: Re: Coding challenge: Space-separated constants

----- Original Message ----- 
From: "Joel VanderWerf" <vjoel@PATH.Berkeley.EDU>
To: "ruby-talk ML" <ruby-talk@ruby-lang.org>
Sent: Monday, February 24, 2003 1:17 AM
Subject: Re: Coding challenge: Space-separated constants


> Inefficient, but it seems to work...

[snip Joel's code]

I based this on Joel Vanderwerf's idea and made 
the following adjustments.

1. I divide the whole string into "pieces" that
are each either whitespace or "blackspace" :)
2. I work a piece at a time instead of a char
at a time

I'll bet this is faster, though I haven't tried
a speed comparison.

I also added detection of malformed constants.

Code below. Improvement/critique welcome.

Hal


class String
  def values
    pieces = self.scan(/[ \t]+|[^ \t]+/)
    vals = []
    str = ""
    while pieces[0] do
      piece = pieces.shift
      str << piece
      if str =~ /^[ \t]+$/   # whitespace only
        str = ""
        next
      end
      begin 
        vals << eval(str)
        str = ""
      rescue Exception
        if pieces[0]
          next
        else
          raise "Bad value near #{str}"
        end
      end
    end
    vals
  end
end

line1 = <<EOF
234 3.14 "John Smith" "Jane Doe"  'Bob Dole' true nil
EOF
p line1.values

line2 = <<EOF
%w[alpha beta gamma] %q[This'" is'" "" '' only a test.]
EOF
p line2.values

line3 = " 234 345.678 'John"   # Unterminated quote
p line3.values