Class: ABNF::Rep

Inherits:
Elt
  • Object
show all
Defined in:
lib/abnf/abnf.rb,
lib/abnf/regexp.rb,
lib/abnf/regexp.rb,
lib/abnf/grammar.rb

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from Elt

#*, #+, #empty_sequence?, #empty_set?, #remove_left_recursion, #remove_right_recursion, #rep, #|

Constructor Details

#initialize(elt, min = 0, max = nil, greedy = true) ⇒ Rep

Returns a new instance of Rep.



136
137
138
139
140
141
 
# File 'lib/abnf/grammar.rb', line 136

def initialize(elt, min=0, max=nil, greedy=true)
  @elt = elt
  @min = min
  @max = max
  @greedy = greedy
end

Instance Attribute Details

#elt ⇒ Object (readonly)

Returns the value of attribute elt.



142
143
144
 
# File 'lib/abnf/grammar.rb', line 142

def elt
  @elt
end

#greedy ⇒ Object (readonly)

Returns the value of attribute greedy.



142
143
144
 
# File 'lib/abnf/grammar.rb', line 142

def greedy
  @greedy
end

#max ⇒ Object (readonly)

Returns the value of attribute max.



142
143
144
 
# File 'lib/abnf/grammar.rb', line 142

def max
  @max
end

#min ⇒ Object (readonly)

Returns the value of attribute min.



142
143
144
 
# File 'lib/abnf/grammar.rb', line 142

def min
  @min
end

Class Method Details

._new ⇒ Object 



123
 
# File 'lib/abnf/grammar.rb', line 123

alias _new new

.new(elt, min = 0, max = nil, greedy = true) ⇒ Object 



126
127
128
129
130
131
132
133
134
 
# File 'lib/abnf/grammar.rb', line 126

def Rep.new(elt, min=0, max=nil, greedy=true)
  return EmptySequence if min == 0 && max == 0
  return elt if min == 1 && max == 1
  return EmptySequence if elt.empty_sequence?
  if elt.empty_set?
    return min == 0 ? EmptySequence : EmptySet
  end
  Rep._new(elt, min, max, greedy)
end

Instance Method Details

#each_var(&block) ⇒ Object 



144
 
# File 'lib/abnf/grammar.rb', line 144

def each_var(&block) @elt.each_var(&block) end

#recursion(syms, lhs) ⇒ Object 



316
317
318
 
# File 'lib/abnf/regexp.rb', line 316

def recursion(syms, lhs)
  @elt.recursion(syms, lhs) == NonRecursion ? NonRecursion : OtherRecursion
end

#regexp_tree ⇒ Object 



392
 
# File 'lib/abnf/regexp.rb', line 392

def regexp_tree() @elt.regexp_tree.rep(min, max, greedy) end

#remove_just_recursion(n) ⇒ Object 



320
321
322
 
# File 'lib/abnf/regexp.rb', line 320

def remove_just_recursion(n)
  self
end

#split_left_recursion(n) ⇒ Object Also known as: split_right_recursion 



324
325
326
 
# File 'lib/abnf/regexp.rb', line 324

def split_left_recursion(n)
  [self, EmptySet]
end

#split_recursion(n) ⇒ Object 



329
330
331
 
# File 'lib/abnf/regexp.rb', line 329

def split_recursion(n)
  [EmptySet, self, EmptySet]
end

#subst_var(&block) ⇒ Object 



145
 
# File 'lib/abnf/grammar.rb', line 145

def subst_var(&block) Rep.new(@elt.subst_var(&block), min, max, greedy) end

#useful?(useful_names) ⇒ Boolean

Returns:

  • (Boolean) 


122
 
# File 'lib/abnf/abnf.rb', line 122

def useful?(useful_names) @min == 0 ? true : @elt.useful?(useful_names) end