Module: MDOM::Parser

Extended by:
Parser
Included in:
Parser
Defined in:
lib/mdom/parser.rb

Defined Under Namespace

Classes: Reader

Constant Summary collapse

HEADING_RE = 
/\A(\#{1,6})[ \t]+(.*?)[ \t]*\z/.freeze
SETEXT_RE = 
/\A\s*([=-]+)\s*\z/.freeze
FENCE_RE = 
/\A([ ]{0,3})(`{3,}|~{3,})(.*)\z/.freeze
HRULE_RE = 
/\A\s*((\*\s*){3,}|(-\s*){3,}|(_\s*){3,})\z/.freeze
QUOTE_RE = 
/\A[ ]{0,3}>[ \t]?(.*)\z/.freeze
LIST_RE = 
/\A([ ]*)([-*+])([ \t]+)(.*)\z/.freeze
ORDERED_RE = 
/\A([ ]*)(\d{1,9})([.)])([ \t]+)(.*)\z/.freeze
TASK_RE = 
/\A\[([ xX])\][ \t]+(.*)\z/.freeze

Instance Method Summary collapse

Instance Method Details

#expand_leading_tabs(line) ⇒ Object

Expand leading tab characters in line into spaces at 4-column tab stops. This normalizes list/quote indentation so the block parser can reason about column widths, while leaving the non-indentation content (including tabs inside code or text) untouched. A tab stop positions the next character at the next multiple of 4.



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# File 'lib/mdom/parser.rb', line 33

def expand_leading_tabs(line)
  i = 0
  col = 0
  out = +""
  while i < line.length
    ch = line[i]
    case ch
    when " "
      out << " "
      col += 1
      i += 1
    when "\t"
      target = (col / 4 + 1) * 4
      out << " " * (target - col)
      col = target
      i += 1
    else
      out << line[i..]
      break
    end
  end
  out
end

#normalize(source) ⇒ Object 



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# File 'lib/mdom/parser.rb', line 20

def normalize(source)
  s = source.to_s
  s = s.gsub(/\r\n?/, "\n").sub(/\A\n+/, "").chomp
  return [] if s.empty?

  s.split("\n", -1).map { |line| expand_leading_tabs(line) }
end

#read(source) ⇒ Object 



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# File 'lib/mdom/parser.rb', line 16

def read(source)
  Reader.new(normalize(source)).parse
end