```ruby
require 'guard'
require 'guard/guard'
require 'less'

require File.dirname(__FILE__) + "/less/version"

module Guard
  class Less < Guard

    # ================
    # = Guard method =
    # ================
    def initialize(watchers=[], options={})
      super
      @all_after_change = options.delete(:all_after_change)
      @all_on_start = options.delete(:all_on_start)
    end

    def start
      UI.info "Guard::Less #{LessVersion::VERSION} is on the job!"
      run_all unless @all_on_start == false
    end

    # Call with Ctrl-/ signal
    # This method should be principally used for long action like running all specs/tests/...
    def run_all
       patterns = @watchers.map { |w| w.pattern }
       files = Dir.glob('**/*.*')
       paths = []
       files.each do |file|
         patterns.each do |pattern|
           paths << file if file.match(Regexp.new(pattern))
         end
       end
       run(paths)
    end

    # Call on file(s) modifications
    def run_on_change(paths)
      run_all if run(paths) && (@all_after_change != false)
    end

    def run(paths)
      last_passed = false
      paths.each do |file|
        unless File.basename(file)[0] == "_"
          UI.info "lessc - #{file}\n"
          last_passed = system("lessc #{file} --verbose")
        end
      end
      last_passed
    end

  end
end
```

Fix partial exclusion for Ruby 1.8
user
```ruby
require 'guard'
require 'guard/guard'
require 'less'

require File.dirname(__FILE__) + "/less/version"

module Guard
  class Less < Guard

    # ================
    # = Guard method =
    # ================
    def initialize(watchers=[], options={})
      super
      @all_after_change = options.delete(:all_after_change)
      @all_on_start = options.delete(:all_on_start)
    end

    def start
      UI.info "Guard::Less #{LessVersion::VERSION} is on the job!"
      run_all unless @all_on_start == false
    end

    # Call with Ctrl-/ signal
    # This method should be principally used for long action like running all specs/tests/...
    def run_all
       patterns = @watchers.map { |w| w.pattern }
       files = Dir.glob('**/*.*')
       paths = []
       files.each do |file|
         patterns.each do |pattern|
           paths << file if file.match(Regexp.new(pattern))
         end
       end
       run(paths)
    end

    # Call on file(s) modifications
    def run_on_change(paths)
      run_all if run(paths) && (@all_after_change != false)
    end

    def run(paths)
      last_passed = false
      paths.each do |file|
        unless File.basename(file)[0,1] == "_"
          UI.info "lessc - #{file}\n"
          last_passed = system("lessc #{file} --verbose")
        end
      end
      last_passed
    end

  end
end
```
assistant