Class: RText::Frontend::Context

Inherits:
Object
  • Object
show all
Defined in:
lib/rtext/frontend/context.rb

Instance Method Summary collapse

Instance Method Details

#extract(lines, pos) ⇒ Object

lines: all lines from the beginning up to and including the current line pos: position of the cursor in the last lines returns the extracted lines and the new position in the last line



9
10
11
12
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
 
# File 'lib/rtext/frontend/context.rb', line 9

def extract(lines, pos)
  lines = filter_lines(lines)
  return nil if lines.nil?
  lines, new_pos = join_lines(lines, pos)
  non_ignored_lines = 0
  array_nesting = 0
  block_nesting = 0
  last_element_line = 0
  result = []
  lines.reverse.each_with_index do |l, i|
    if i == 0
      result.unshift(l)
    else
      non_ignored_lines += 1
      case l.strip[-1..-1]
      when "{"
        if block_nesting > 0
          block_nesting -= 1 
        elsif block_nesting == 0
          result.unshift(l)
          last_element_line = non_ignored_lines
        end
      when "}"
        block_nesting += 1
      when "["
        if array_nesting > 0
          array_nesting -= 1
        elsif array_nesting == 0
          result.unshift(l)
        end
      when "]"
        array_nesting += 1
      when ":"
        # lable directly above element

        if non_ignored_lines == last_element_line + 1
          result.unshift(l)
        end
      end
    end
  end
  [result, new_pos]
end

#filter_lines(lines) ⇒ Object 



52
53
54
55
56
57
58
59
60
61
62
63
 
# File 'lib/rtext/frontend/context.rb', line 52

def filter_lines(lines)
  ret = []
  lines.each_with_index do |line, i|
    ls = line.strip
    if ls.start_with?("@") || ls.start_with?("#")
      return nil if i+1 == lines.length
    else
      ret << line
    end
  end
  ret
end

#join_lines(lines, pos) ⇒ Object

when joining two lines, all whitespace is preserved in order to simplify the algorithm whitespace after a backslash is also preserved, only the backslash itself is removed note that whitespace left of the cursor is important for proper context calculation



68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
 
# File 'lib/rtext/frontend/context.rb', line 68

def join_lines(lines, pos)
  outlines = []
  while lines.size > 0
    outlines << lines.shift
    while lines.size > 0 && 
        (outlines.last =~ /[,\\]\s*$/ || 
          # don't join after a child label

          (outlines.last !~ /^\s*\w+:/ &&
            (outlines.last =~ /\[\s*$/ ||
            (lines.first =~ /^\s*\]/ && outlines.last =~ /\[/))))
      l = lines.shift
      outlines.last.gsub!("\\","")
      if lines.size == 0
        # the prefix might have whitespace on the

        # right hand side which is relevant for the position

        pos = outlines.last.size + pos
      end
      outlines.last.concat(l)
    end
  end
  [outlines, pos]
end