Problem with .each do

ruby-talk
1

Hiya. The book does things this way, so why doesn't it work for me? What's going on?

def fromWeb(site, url)
  # get data from website
  h = Net::HTTP.new(site, 80)
  resp, data=h.get(url, nil)

  # process data
  data.each do <- point of second error
    >line>
    if /DGM_navigation/ =~ line do
      # decode page lineage
      step=Array.new
      astep, line = getNextWord(line)
      while astep != nil
        step.push(astep)
        astep, line = getNextWord(line)
      end
      puts "Page Lineage"
      step.each do
        >astep>
        step.each do
          put " "
        end
        puts astep
      end
    end # end DGM_naviation
  end # end data.each <- gets "undefined method 'line'", from the second error point above
end # end def fromWeb

def getNextWord(line)
  i1 = />\w+</ =~ line

  string_wanted=$&[1..$&.length-1]
  string_remaining=$'
  return string_wanted, string_remaining
end

2

Lady Michelle Bhaal <michelle@corax.com.au> writes:

Hiya. The book does things this way, so why doesn't it work for me?
What's going on?

def fromWeb(site, url)
  # get data from website
  h = Net::HTTP.new(site, 80)
  resp, data=h.get(url, nil)

  # process data
  data.each do <- point of second error
    >line>
              [ ... etc. ... ]
  end # end data.each <- gets "undefined method 'line'", from the second

It turns out that Net::Http#get no longer returns a pair of values. It
has changed between ruby version 1.6 (from the edition of the book that
you probably have) and 1.8. This is explained in the method's latest
documentation (from
http://www.ruby-doc.org/stdlib/libdoc/net/http/rdoc/index.html\):

  get(path, initheader = nil, dest = nil) {|+body_segment+| ...}

  Gets data from path on the connected-to host. header must be a Hash
  like { 'Accept' => '*/*', ... }.

  In version 1.1 (ruby 1.6), this method returns a pair of objects, a
  Net::HTTPResponse object and the entity body string. In version 1.2
  (ruby 1.8), this method returns a Net::HTTPResponse object.

  If called with a block, yields each fragment of the entity body in
  turn as a string as it is read from the socket. Note that in this
  case, the returned response object will not contain a (meaningful)
  body.

  dest argument is obsolete. It still works but you must not use it.

  In version 1.1, this method might raise an exception for 3xx
  (redirect). In this case you can get a HTTPResponse object by
  "anException.response".

  In version 1.2, this method never raises exception.

    # version 1.1 (bundled with Ruby 1.6)
    response, body = http.get('/index.html')

    # version 1.2 (bundled with Ruby 1.8 or later)
    response = http.get('/index.html')

    # using block
    File.open('result.txt', 'w') {|f|
      http.get('/~foo/') do |str|
        f.write str
      end
    }

See also Net::HTTPResponse within that same documentation.

···

--
Lloyd Zusman
ljz@asfast.com
God bless you.

3

Lady Michelle Bhaal wrote:

Hiya. The book does things this way, so why doesn't it work for me? What's going on?

def fromWeb(site, url)
    # get data from website
    h = Net::HTTP.new(site, 80)
    resp, data=h.get(url, nil)

    # process data
    data.each do <- point of second error
        >line>

Try `data.each do |line|'. It may be the line break that's causing trouble.

        if /DGM_navigation/ =~ line do
            # decode page lineage
            step=Array.new
            astep, line = getNextWord(line)
            while astep != nil
                step.push(astep)
                astep, line = getNextWord(line)
            end
            puts "Page Lineage"
            step.each do
                >astep>

Same here.

                step.each do
                    put " "
                end
                puts astep
            end
        end # end DGM_naviation
    end # end data.each <- gets "undefined method 'line'", from the second error point above
end # end def fromWeb

def getNextWord(line)
    i1 = />\w+</ =~ line

    string_wanted=$&[1..$&.length-1]
    string_remaining=$'
    return string_wanted, string_remaining
end

Cheers,
Daniel

4

Sorry, it actually seems to work even with the line break. My bad.

Cheers,
Daniel