Class: Packcr::Node::PredicateNode

Inherits:
Packcr::Node show all
Defined in:
lib/packcr/node/predicate_node.rb,
lib/packcr/generated/node/predicate_node.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods inherited from Packcr::Node

#alt, #link_references, #reversible?, #seq, #sequence?, #setup, #setup_rule, #verify_captures, #verify_variables

Constructor Details

#initialize(expr = nil, neg = false) ⇒ PredicateNode

Returns a new instance of PredicateNode.



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# File 'lib/packcr/node/predicate_node.rb', line 6

def initialize(expr = nil, neg = false)
  super()
  @expr = expr
  @neg = neg
end

Instance Attribute Details

#expr ⇒ Object

Returns the value of attribute expr.



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# File 'lib/packcr/node/predicate_node.rb', line 4

def expr
  @expr
end

#neg ⇒ Object

Returns the value of attribute neg.



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# File 'lib/packcr/node/predicate_node.rb', line 4

def neg
  @neg
end

Instance Method Details

#debug_dump(indent = 0) ⇒ Object 



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# File 'lib/packcr/node/predicate_node.rb', line 12

def debug_dump(indent = 0)
  $stdout.print "#{" " * indent}Predicate(neg:#{neg ? 1 : 0}) {\n"
  expr.debug_dump(indent + 2)
  $stdout.print "#{" " * indent}}\n"
end

#generate_code(gen, onfail, indent, bare, oncut: nil) ⇒ Object 



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# File 'lib/packcr/node/predicate_node.rb', line 18

def generate_code(gen, onfail, indent, bare, oncut: nil)
  if neg
    gen.write Packcr.format_code(get_neg_code(gen, onfail, indent, bare, oncut), indent: indent, unwrap: bare)
  else
    gen.write Packcr.format_code(get_code(gen, onfail, indent, bare, oncut), indent: indent, unwrap: bare)
  end
end

#get_code(gen, onfail, indent, bare, oncut) ⇒ Object 



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# File 'lib/packcr/generated/node/predicate_node.rb', line 4

def get_code(gen, onfail, indent, bare, oncut)
  case gen.lang
  when :c
    erbout = +""
    l = gen.next_label
    m = gen.next_label
    r = expr.reachability
    erbout << "{\n    const size_t p = ctx->position_offset;\n".freeze

    if gen.location
      erbout << "    const packcr_location_t p_loc = ctx->position_offset_loc;\n".freeze
    end
    erbout << "#{gen.generate_code(expr, l, 4, false)}".freeze
    if r != Packcr::CODE_REACH__ALWAYS_FAIL
      erbout << "    ctx->position_offset = p;\n".freeze

      if gen.location
        erbout << "    ctx->position_offset_loc = p_loc;\n".freeze
      end
    end
    if r == Packcr::CODE_REACH__BOTH
      erbout << "    goto L#{format("%04d", m)};\n".freeze
    end
    if r != Packcr::CODE_REACH__ALWAYS_SUCCEED
      erbout << "L#{format("%04d", l)}:;\n    ctx->position_offset = p;\n".freeze

      if gen.location
        erbout << "    ctx->position_offset_loc = p_loc;\n".freeze
      end
      erbout << "    goto L#{format("%04d", onfail)};\n".freeze
    end
    if r == Packcr::CODE_REACH__BOTH
      erbout << "L#{format("%04d", m)}:;\n".freeze
    end
    erbout << "}\n".freeze

    erbout
  when :rb
    erbout = +""
    l = gen.next_label
    m = gen.next_label
    r = expr.reachability
    erbout << "catch(#{m}) do\n  pos#{gen.level} = @position_offset\n".freeze

    if gen.location
      erbout << "  p_loc#{gen.level} = @position_offset_pos\n".freeze
    end
    erbout << "  catch(#{l}) do\n#{gen.generate_code(expr, l, 4, false)}".freeze
    if r != Packcr::CODE_REACH__ALWAYS_FAIL
      erbout << "    @position_offset = pos#{gen.level}\n".freeze

      if gen.location
        erbout << "    @position_offset_loc = p_loc#{gen.level}\n".freeze
      end
    end
    if r == Packcr::CODE_REACH__BOTH
      erbout << "    throw(#{m})\n".freeze
    end
    erbout << "  end\n".freeze

    if r != Packcr::CODE_REACH__ALWAYS_SUCCEED
      erbout << "  @position_offset = pos#{gen.level}\n".freeze

      if gen.location
        erbout << "  @position_offset_loc = p_loc#{gen.level}\n".freeze
      end
      erbout << "  throw(#{onfail})\n".freeze
    end
    erbout << "end\n".freeze

    erbout
  end
end

#get_neg_code(gen, onfail, indent, bare, oncut) ⇒ Object 



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# File 'lib/packcr/generated/node/predicate_node.rb', line 78

def get_neg_code(gen, onfail, indent, bare, oncut)
  case gen.lang
  when :c
    erbout = +""
    l = gen.next_label
    r = expr.reachability
    erbout << "{\n    const size_t p = ctx->position_offset;\n".freeze

    if gen.location
      erbout << "    const packcr_location_t p_loc = ctx->position_offset_loc;\n".freeze
    end
    erbout << "#{gen.generate_code(expr, l, 4, false)}".freeze
    if r != Packcr::CODE_REACH__ALWAYS_FAIL
      erbout << "    ctx->position_offset = p;\n".freeze

      if gen.location
        erbout << "    ctx->position_offset_loc = p_loc;\n".freeze
      end
      erbout << "    goto L#{format("%04d", onfail)};\n".freeze
    end
    if r != Packcr::CODE_REACH__ALWAYS_SUCCEED
      erbout << "L#{format("%04d", l)}:;\n    ctx->position_offset = p;\n".freeze

      if gen.location
        erbout << "    ctx->position_offset_loc = p_loc;\n".freeze
      end
    end
    erbout << "}\n".freeze

    erbout
  when :rb
    erbout = +""
    l = gen.next_label
    r = expr.reachability
    erbout << "pos#{gen.level} = @position_offset\n".freeze

    if gen.location
      erbout << "p_loc#{gen.level} = @position_offset_loc\n".freeze
    end
    erbout << "catch(#{l}) do\n#{gen.generate_code(expr, l, 2, false)}".freeze
    if r != Packcr::CODE_REACH__ALWAYS_FAIL
      erbout << "  @position_offset = pos#{gen.level}\n".freeze

      if gen.location
        erbout << "  @position_offset_loc = p_loc#{gen.level}\n".freeze
      end
      erbout << "  throw(#{onfail})\n".freeze
    end
    erbout << "end\n".freeze

    if r != Packcr::CODE_REACH__ALWAYS_SUCCEED
      erbout << "@position_offset = pos#{gen.level}\n".freeze

      if gen.location
        erbout << "@position_offset_loc = p_loc#{gen.level}\n".freeze
      end
    end
    erbout
  end
end

#nodes ⇒ Object 



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# File 'lib/packcr/node/predicate_node.rb', line 34

def nodes
  [expr]
end

#reachability ⇒ Object 



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# File 'lib/packcr/node/predicate_node.rb', line 26

def reachability
  if neg
    -expr.reachability
  else
    expr.reachability
  end
end

#to_h ⇒ Object 



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# File 'lib/packcr/node/predicate_node.rb', line 38

def to_h
  {
    type: :predicate,
    expr: expr&.to_h,
    neg: neg,
  }
end