Class: Parser

Inherits:
Object
  • Object
show all
Includes:
Types
Defined in:
lib/rpl/parser.rb

Class Method Summary collapse

Methods included from Types

new_object

Class Method Details

.parse(input) ⇒ Object 



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
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
 
# File 'lib/rpl/parser.rb', line 15

def self.parse( input )
  unless input.index("\n").nil?
    input = input.split("\n")
                 .map do |line|
      comment_begin_index = line.index('@')

      case comment_begin_index
      when nil
        line
      when 0
        ''
      else
        line[0..(comment_begin_index - 1)]
      end
    end
                 .join(' ')
  end

  splitted_input = input.split

  # 2-passes:
  # 1. regroup strings, lists, complexes, names and programs
  opened_programs = 0
  closed_programs = 0

  opened_lists = 0
  closed_lists = 0

  opened_complexes = 0
  closed_complexes = 0

  string_delimiters = 0

  name_delimiters = 0

  regrouping = false

  regrouped_input = []
  splitted_input.each do |elt|
    if elt[0] == '«'
      opened_programs += 1
      elt.gsub!( '«', '« ') if elt.length > 1 && elt[1] != ' '
    elsif elt[0] == '{'
      opened_lists += 1
      elt.gsub!( '{', '{ ') if elt.length > 1 && elt[1] != ' '
    elsif elt[0] == '('
      opened_complexes += 1
      elt.gsub!( '( ', '(') if elt.length > 1 && elt[1] == ' '
    elsif elt[0] == '"' && elt.length > 1
      string_delimiters += 1
    elsif elt[0] == "'" && elt.length > 1
      name_delimiters += 1
    end

    elt = "#{regrouped_input.pop}#{opened_complexes > closed_complexes ? '' : ' '}#{elt}".strip if regrouping

    regrouped_input << elt

    case elt[-1]
    when '»'
      closed_programs += 1
      elt.gsub!( '»', ' »') if elt.length > 1 && elt[-2] != ' '
    when '}'
      closed_lists += 1
      elt.gsub!( '}', ' }') if elt.length > 1 && elt[-2] != ' '
    when ')'
      closed_complexes += 1
      elt.gsub!( ' )', ')') if elt.length > 1 && elt[-2] == ' '
    when '"'
      string_delimiters += 1
    when "'"
      name_delimiters += 1
    end

    regrouping = string_delimiters.odd? || name_delimiters.odd? || (opened_programs > closed_programs) || (opened_lists > closed_lists) || (opened_complexes > closed_complexes)
  end

  # 2. parse
  regrouped_input.map do |element|
    if RplBoolean.can_parse?( element )
      Types.new_object( RplBoolean, element )
    elsif RplNumeric.can_parse?( element )
      Types.new_object( RplNumeric, element )
    elsif RplComplex.can_parse?( element )
      Types.new_object( RplComplex, element )
    elsif RplList.can_parse?( element )
      Types.new_object( RplList, element )
    elsif RplString.can_parse?( element )
      Types.new_object( RplString, element )
    elsif RplProgram.can_parse?( element )
      Types.new_object( RplProgram, element )
    elsif RplName.can_parse?( element )
      Types.new_object( RplName, element )
    end
  end
end