# File lib/tilt.rb, line 71
 71:   def self.[](file)
 72:     pattern = file.to_s.downcase
 73:     until pattern.empty? || registered?(pattern)
 74:       pattern = File.basename(pattern)
 75:       pattern.sub!(/^[^.]*\.?/, '')
 76:     end
 77: 
 78:     # Try to find a preferred engine.
 79:     klass = @preferred_mappings[pattern]
 80:     return klass if klass
 81: 
 82:     # Fall back to the general list of mappings.
 83:     klasses = @template_mappings[pattern]
 84: 
 85:     # Try to find an engine which is already loaded.
 86:     template = klasses.detect do |klass|
 87:       if klass.respond_to?(:engine_initialized?)
 88:         klass.engine_initialized?
 89:       end
 90:     end
 91: 
 92:     return template if template
 93: 
 94:     # Try each of the classes until one succeeds. If all of them fails,
 95:     # we'll raise the error of the first class.
 96:     first_failure = nil
 97: 
 98:     klasses.each do |klass|
 99:       begin
100:         klass.new { '' }
101:       rescue Exception => ex
102:         first_failure ||= ex
103:         next
104:       else
105:         return klass
106:       end
107:     end
108: 
109:     raise first_failure if first_failure
110:   end

    # File lib/tilt.rb, line 8
 8:   def self.mappings
 9:     @template_mappings
10:   end

    # File lib/tilt.rb, line 61
61:   def self.new(file, line=nil, options={}, &block)
62:     if template_class = self[file]
63:       template_class.new(file, line, options, &block)
64:     else
65:       fail "No template engine registered for #{File.basename(file)}"
66:     end
67:   end

    # File lib/tilt.rb, line 12
12:   def self.normalize(ext)
13:     ext.to_s.downcase.sub(/^\./, '')
14:   end

    # File lib/tilt.rb, line 40
40:   def self.prefer(template_class, *extensions)
41:     if extensions.empty?
42:       mappings.each do |ext, klasses|
43:         @preferred_mappings[ext] = template_class if klasses.include? template_class
44:       end
45:     else
46:       extensions.each do |ext|
47:         ext = normalize(ext)
48:         register(template_class, ext)
49:         @preferred_mappings[ext] = template_class
50:       end
51:     end
52:   end

    # File lib/tilt.rb, line 17
17:   def self.register(template_class, *extensions)
18:     if template_class.respond_to?(:to_str)
19:       # Support register(ext, template_class) too
20:       ext = template_class
21:       template_class = extensions[0]
22:       extensions = [ext]
23:     end
24: 
25:     extensions.each do |ext|
26:       ext = normalize(ext)
27:       mappings[ext].unshift(template_class).uniq!
28:     end
29:   end

    # File lib/tilt.rb, line 55
55:   def self.registered?(ext)
56:     mappings.key?(ext.downcase) && !mappings[ext.downcase].empty?
57:   end