in reply to Nested list items

You need to write a parser. 

state = []
ARGF.each do |line|
  state.push :input    if line =~ /<input>/
  state.push :ordered  if line =~ /<ordered-list>/
  state.push :bulleted if line =~ /<bulleted-list>/
  state.pop            if line =~ /<end-list>/ or
                          line =~ /<\/input>/

  if line =~ /<item>/
    case state.last
    when :ordered
      line.gsub!( /<item>/, "<ordered-item>" )
    when :bulleted
      line.gsub!( /<item>/, "<bulleted-item>" )
    else
      ## do nothing
    end
  end

  puts line
end

[download]

Updated: Tweaked to actually run . . . and again to tweak state transitions to look prettier.

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Re^2: Nested list items
by ikegami (Patriarch) on Sep 21, 2006 at 16:02 UTC

    Here's the Perl5 implementation of Fletch's code. 

    my @state;
while (<>) {
   push @state, 'input'    if /<input>/;
   push @state, 'ordered'  if /<ordered-list>/;
   push @state, 'bulleted' if /<bulleted-list>/;
   pop @state              if /<end-list>/ || /<\/input>/;

   my $state = $state[$#state];
   s/<item>/<ordered-item>/g  if $state eq 'ordered';
   s/<item>/<bulleted-item>/g if $state eq 'bulleted';

   print;
}

    [download]

    Note that it has problems handling lines with multiple tags.

[reply]
[d/l]
Re^2: Nested list items
by jdtoronto (Prior) on Sep 21, 2006 at 16:24 UTC
    Looks nice, but what the heck language is it?
[reply]

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