Trace line and column numbers in SAX-parser about ox

[ohler55]

Seems reasonable but I do not want to use globals as it breaks multithreading. Let me mull over other options.

[take-five]

Oh, I've meant that __line__ and __column__ are Ox::Sax instance methods

[ohler55]

Still doesn't work as Ox::Sax is created by the user, not the parser. The handler does not have to inherit from that class either. I took a slight different approach. If the handler has an @line instance variable it is set before any callback. Same for @column. If there are no callback then they are not set and there is no overhead. Look for it in 1.9.0 later tonight.

[ohler55]

Take a look at 1.9.0.

[take-five]

Wow, thanks for quick work!

Line numbers work absolutely correctly, but I do not completely understand, how column numbers are calculated.

Look:

<top name="sample">
  <middle name="second">
    <bottom name="third"/>
  </middle>
</top>

class Sample < ::Ox::Sax
  attr_reader :line, :column
  def initialize
    @line, @column = nil, nil
  end

  def start_element(name); puts "start: #{name.inspect} at #{line}:#{column}";        end
  def end_element(name);   puts "end: #{name.inspect} at #{line}:#{column}";          end
  def attr(name, value);   puts "  #{name.inspect} => #{value.inspect} at #{line}:#{column}"; end
  def text(value);         puts "text #{value.inspect} at #{line}:#{column}";         end
end

Here is the output:

start: :top at 1:6 # everything is clear here, we're at the beginning of "name" attribute
  :name => "sample" at 1:20
start: :middle at 2:12 # that's not clear to me, we're at the "a" letter of "name" attribute
  :name => "second" at 2:26
start: :bottom at 3:14
  :name => "third" at 3:27
end: :bottom at 3:29 # strange: third line is 27 chars length
end: :middle at 4:12
end: :top at 5:7

[ohler55]

Does seem off. It will be a couple of days before I can look at it though. Probably reading white space.

Alexey Mihaylov [email protected] wrote:

Wow, thanks for quick job!

Line numbers work absolutely correctly, but I do not completely
understand, how column numbers are calculated.

Look:

<top name="sample">
 <middle name="second">
   <bottom name="third"/>
 </middle>
</top>

class Sample < ::Ox::Sax
 attr_reader :line, :column
 def initialize
   @line, @column = nil, nil
 end

def start_element(name); puts "start: #{name.inspect} at
#{line}:#{column}";        end
def end_element(name);   puts "end: #{name.inspect} at
#{line}:#{column}";          end
def attr(name, value);   puts "  #{name.inspect} => #{value.inspect} at
#{line}:#{column}"; end
def text(value);         puts "text #{value.inspect} at
#{line}:#{column}";         end
end

Here is the output:

start: :top at 1:6 # everything is clear here, we're at the beginning
of "name" attribute
 :name => "sample" at 1:20
start: :middle at 2:12 # that's not clear to me, we're at the "a"
letter of "name" attribute
 :name => "second" at 2:26
start: :bottom at 3:14
 :name => "third" at 3:27
end: :bottom at 3:29 # strange: third line is 27 chars length
end: :middle at 4:12
end: :top at 5:7

---

Reply to this email directly or view it on GitHub:
#44 (comment)

[take-five]

Anyway, thanks for your great work!

[ohler55]

Change the line numbers to be the start of each component and also fixed the bug of the column being too high in release 1.9.1.

[take-five]

I'll take a look today

[take-five]

Works great!

Thank you very, very much for your great work!

[ohler55]

Thanks for finding bugs and for the suggestion.