class Racc::Grammar::DefinitionEnv - racc: Ruby Standard Library Documentation

# class Racc::Grammar::DefinitionEnv

### Public Class Methods

new() click to toggle source

    # File racc-1.8.1/lib/racc/grammar.rb, line 210
    def initialize
      @grammar = Grammar.new
      @seqs = Hash.new(0)
      @delayed = []
    end

### Public Instance Methods

_(&block)
Alias for: action
_add(target, x) click to toggle source

    # File racc-1.8.1/lib/racc/grammar.rb, line 244
    def _add(target, x)
      case x
      when Sym
        @delayed.each do |rule|
          rule.replace x, target if rule.target == x
        end
        @grammar.symboltable.delete x
      else
        x.each_rule do |r|
          r.target = target
          @grammar.add r
        end
      end
      flush_delayed
    end

_added?(sym) click to toggle source

    # File racc-1.8.1/lib/racc/grammar.rb, line 264
    def _added?(sym)
      @grammar.added?(sym) or @delayed.detect {|r| r.target == sym }
    end

_delayed_add(rule) click to toggle source

    # File racc-1.8.1/lib/racc/grammar.rb, line 260
    def _delayed_add(rule)
      @delayed.push rule
    end

_intern(x) click to toggle source

    # File racc-1.8.1/lib/racc/grammar.rb, line 323
    def _intern(x)
      case x
      when Symbol, String
        @grammar.intern(x)
      when Racc::Sym
        x
      else
        raise TypeError, "wrong type #{x.class} (expected Symbol/String/Racc::Sym)"
      end
    end

action(&block) click to toggle source

    # File racc-1.8.1/lib/racc/grammar.rb, line 284
    def action(&block)
      id = "@#{@seqs["action"] += 1}".intern
      _delayed_add Rule.new(@grammar.intern(id), [], UserAction.proc(block))
      id
    end

Also aliased as: _
flush_delayed() click to toggle source

    # File racc-1.8.1/lib/racc/grammar.rb, line 268
    def flush_delayed
      return if @delayed.empty?
      @delayed.each do |rule|
        @grammar.add rule
      end
      @delayed.clear
    end

grammar() click to toggle source

    # File racc-1.8.1/lib/racc/grammar.rb, line 216
    def grammar
      flush_delayed
      @grammar.each do |rule|
        if rule.specified_prec
          rule.specified_prec = @grammar.intern(rule.specified_prec)
        end
      end
      @grammar.init
      @grammar
    end

many(sym, &block) click to toggle source

    # File racc-1.8.1/lib/racc/grammar.rb, line 298
    def many(sym, &block)
      _defmetasyntax("many", _intern(sym), block) {|target|
          seq() { [] }\
        | seq(target, sym) {|list, x| list.push x; list }
      }
    end

many1(sym, &block) click to toggle source

    # File racc-1.8.1/lib/racc/grammar.rb, line 305
    def many1(sym, &block)
      _defmetasyntax("many1", _intern(sym), block) {|target|
          seq(sym) {|x| [x] }\
        | seq(target, sym) {|list, x| list.push x; list }
      }
    end

method_missing(mid, *args, &block) click to toggle source
Calls superclass method

    # File racc-1.8.1/lib/racc/grammar.rb, line 233
    def method_missing(mid, *args, &block)
      unless mid.to_s[-1,1] == '='
        super   # raises NoMethodError
      end
      target = @grammar.intern(mid.to_s.chop.intern)
      unless args.size == 1
        raise ArgumentError, "too many arguments for #{mid} (#{args.size} for 1)"
      end
      _add target, args.first
    end

null(&block) click to toggle source

    # File racc-1.8.1/lib/racc/grammar.rb, line 280
    def null(&block)
      seq(&block)
    end

option(sym, default = nil, &block) click to toggle source

    # File racc-1.8.1/lib/racc/grammar.rb, line 292
    def option(sym, default = nil, &block)
      _defmetasyntax("option", _intern(sym), block) {|target|
        seq() { default } | seq(sym)
      }
    end

precedence_table(&block) click to toggle source

    # File racc-1.8.1/lib/racc/grammar.rb, line 227
    def precedence_table(&block)
      env = PrecedenceDefinitionEnv.new(@grammar)
      env.instance_eval(&block)
      @grammar.end_precedence_declaration env.reverse
    end

separated_by(sep, sym, &block) click to toggle source

    # File racc-1.8.1/lib/racc/grammar.rb, line 312
    def separated_by(sep, sym, &block)
      option(separated_by1(sep, sym), [], &block)
    end

separated_by1(sep, sym, &block) click to toggle source

    # File racc-1.8.1/lib/racc/grammar.rb, line 316
    def separated_by1(sep, sym, &block)
      _defmetasyntax("separated_by1", _intern(sym), block) {|target|
          seq(sym) {|x| [x] }\
        | seq(target, sep, sym) {|list, _, x| list.push x; list }
      }
    end

seq(*list, &block) click to toggle source

    # File racc-1.8.1/lib/racc/grammar.rb, line 276
    def seq(*list, &block)
      Rule.new(nil, list.map {|x| _intern(x) }, UserAction.proc(block))
    end

### Private Instance Methods

_defmetasyntax(type, id, action, &block) click to toggle source

    # File racc-1.8.1/lib/racc/grammar.rb, line 336
    def _defmetasyntax(type, id, action, &block)
      if action
        idbase = "#{type}@#{id}-#{@seqs[type] += 1}"
        target = _wrap(idbase, "#{idbase}-core", action)
        _register("#{idbase}-core", &block)
      else
        target = _register("#{type}@#{id}", &block)
      end
      @grammar.intern(target)
    end

_register(target_name) { |target| ... } click to toggle source

    # File racc-1.8.1/lib/racc/grammar.rb, line 347
    def _register(target_name)
      target = target_name.intern
      unless _added?(@grammar.intern(target))
        yield(target).each_rule do |rule|
          rule.target = @grammar.intern(target)
          _delayed_add rule
        end
      end
      target
    end

_wrap(target_name, sym, block) click to toggle source

    # File racc-1.8.1/lib/racc/grammar.rb, line 358
    def _wrap(target_name, sym, block)
      target = target_name.intern
      _delayed_add Rule.new(@grammar.intern(target),
                            [@grammar.intern(sym.intern)],
                            UserAction.proc(block))
      target
    end