Class: StringParser

Inherits:
Object
  • Object
show all
Defined in:
lib/parser/string.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(line) ⇒ StringParser

Returns a new instance of StringParser.

Raises:

  • (NilValue) 


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# File 'lib/parser/string.rb', line 5

def initialize(line)
  raise NilValue if line.nil?
  raise ExpectedString unless String === line
  @line = line
  @len = @line.length
  @eos = @len == 0 ? true : false
  @i = 0
end

Instance Attribute Details

#eos ⇒ Object (readonly)

Returns the value of attribute eos.



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# File 'lib/parser/string.rb', line 3

def eos
  @eos
end

#i ⇒ Object (readonly)

Returns the value of attribute i.



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# File 'lib/parser/string.rb', line 3

def i
  @i
end

#len ⇒ Object (readonly)

Returns the value of attribute len.



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# File 'lib/parser/string.rb', line 3

def len
  @len
end

#line ⇒ Object (readonly)

Returns the value of attribute line.



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# File 'lib/parser/string.rb', line 3

def line
  @line
end

Instance Method Details

#eos? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/parser/string.rb', line 36

def eos?
  @eos
end

#grab ⇒ Object 



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# File 'lib/parser/string.rb', line 14

def grab
  return nil if @eos
  char = @line[@i]
  @i += 1
  check_eos
  char
end

#next! ⇒ Object 



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# File 'lib/parser/string.rb', line 27

def next!
  @line[@i + 1]
end

#peek ⇒ Object 



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# File 'lib/parser/string.rb', line 40

def peek
  return nil if @eos
  @line[@i]
end

#prev ⇒ Object 



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# File 'lib/parser/string.rb', line 31

def prev
  return nil if @i <= 0
  @line[@i-1]
end

#skip_spaces ⇒ Object 



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# File 'lib/parser/string.rb', line 45

def skip_spaces
  char = nil
  loop do
    char = peek
    break if eos?
    break if char != " "
    char = grab
  end
  char
end

#ungrab ⇒ Object 



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# File 'lib/parser/string.rb', line 22

def ungrab
  @i -= 1
  check_eos
end