tm_comment_blocks.rb

#!/usr/bin/env ruby
str = STDIN.read
start_marker, end_marker = "=begin\n", "\n=end"
out = ''

str.each_line do |line| 
  if str.split.shift == "=begin"
    @uncomment = true  
  end
  
  next if line[/^\=begin/]
  next if line[/^\=end/]
  next if line[/^\n/]
  out << line
end

puts @uncomment? out : start_marker + out + end_marker

Put in the toggle feature. Changed it from a custom start and end tag marker to ruby standard "=begin" "=end" syntax. Doing so removed the need for long 'if' statements. I'll probably make this into a little bundle at some point or another. TM by default allows code folding so adding the '=begin' '=end' syntax lets you fold multi-line comments. As an aside you could use this to comment and fold non-comment code which could be convenient. This prepends "=begin" and appends "=end" and removes them if they are found. Should be used with caution at this point. More to follow.