Module: ZergXcode::Lexer

Defined in:
lib/zerg_xcode/file_format/lexer.rb

Overview

Lexer for flattened object graphs stored in .xcodeproj files.

Class Method Summary collapse

Class Method Details

.tokenize(string) ⇒ Object 



13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
 
# File 'lib/zerg_xcode/file_format/lexer.rb', line 13

def self.tokenize(string)
  
  encoding_match = string.match(/^\/\/ \!\$\*(.*?)\*\$\!/)
  raise "No encoding - #{string[0, 20]}" unless encoding_match
  
  i = encoding_match[0].length
  tokens = [[:encoding, encoding_match[1]]]
  while i < string.length
    # skip comments
    if string[i, 2] == '/*'
      i += 2
      i += 1 while string[i, 2] != '*/'
      i += 2
      next
    end
    
    case string[i, 1]
    when /\s/
      i += 1
    when '(', ')', '{', '}', '=', ';', ','
      tokens << {'(' => :begin_array, ')' => :end_array,
                 '{' => :begin_hash, '}' => :end_hash,
                 '=' => :assign, ';' => :stop, ',' => :comma}[string[i, 1]]
      i += 1
    when '"'
      # string
      i += 1
      token = ''
      while string[i, 1] != '"'
        if string[i, 1] == '\\'
          i += 1
          case string[i, 1]            
          when 'n', 'r', 't'
            token << { 'n' => "\n", 't' => "\t", 'r' => "\r" }[string[i, 1]]
            i += 1 
          when '"', "'", '\\'
            token << string[i]
            i += 1
          else
            raise "Uknown escape sequence \\#{string[i, 20]}"
          end
        else
          token << string[i]
          i += 1
        end
      end
      tokens << [:string, token]
      i += 1
    else
      # something
      len = 0
      len += 1 while /[^\s\t\r\n\f(){}=;,]/ =~ string[i + len, 1]
      tokens << [:symbol, string[i, len]]
      i += len
    end
  end
  return tokens
end