Class: CDDL

Inherits:
Object
  • Object
show all
Defined in:
lib/cddlc.rb,
lib/writer/cddl-writer.rb,
lib/processor/cddl-visitor.rb,
lib/processor/cddl-expander.rb,
lib/processor/cddl-constants.rb,
lib/processor/cddl-undefined.rb,
lib/processor/cddl-flattening.rb

Defined Under Namespace

Classes: MissingGenericError

Constant Summary collapse

DATA_DIR = 
Pathname.new(__FILE__) + "../../data/"
CDDL_INCLUDE_PATH =

empty string is for CDDL::DATA_DIR

ENV["CDDL_INCLUDE_PATH"] || ".:"
SAFE_FN = 
/\A[-._a-zA-Z0-9]+\z/
IMPINC = 
/\A(?:import|include)\z/
IDENTIFIER_RE = 
/\A[A-Za-z@_$]([-.]*[A-Za-z@_$0-9])*\z/
INT_RE = 
/\A0|[-]?[1-9][0-9]*\z/
RULE_OP_TO_CHOICE = 
{"/=" => "tcho", "//=" => "gcho"}
MOGRIFIED_ID_RE = 
/\A\$\.[A-Za-z@_$]([-.]*[A-Za-z@_$0-9])*\z/
@@parser = 
CDDLGRAMMARParser.new

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(ast_, directives_ = []) ⇒ CDDL

Returns a new instance of CDDL.



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# File 'lib/cddlc.rb', line 217

def initialize(ast_, directives_ = [])
  @ast = ast_
  @tree = ast.ast
  @rules = nil                # only fill in if needed
  @directives = directives_
end

Instance Attribute Details

#ast ⇒ Object

Returns the value of attribute ast.



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# File 'lib/cddlc.rb', line 216

def ast
  @ast
end

#directives ⇒ Object

Returns the value of attribute directives.



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# File 'lib/cddlc.rb', line 216

def directives
  @directives
end

#tree ⇒ Object

Returns the value of attribute tree.



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# File 'lib/cddlc.rb', line 216

def tree
  @tree
end

Class Method Details

.cddl_include_path ⇒ Object 



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# File 'lib/cddlc.rb', line 12

def self.cddl_include_path
  CDDL_INCLUDE_PATH.split(":", -1).map {_1 == "" ? CDDL::DATA_DIR : Pathname.new(_1)}
end

.from_cddl(s) ⇒ Object 



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# File 'lib/cddlc.rb', line 60

def self.from_cddl(s)
  ast = @@parser.parse s
  if !ast
    fail self.reason(@@parser, s)
  end
  if $options.cddl2
    directives = s.lines.grep(/^;# /).map(&:chomp).map{|l| l.sub(/^;#\s+/, '').split(/\s+/)}
    # puts directives.to_yaml
  end

  ret = CDDL.new(ast, directives)

  if $options.cddl2
    ret.perform_directives
  end
  ret
end

.read_from_include_path(fn) ⇒ Object 



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# File 'lib/cddlc.rb', line 42

def self.read_from_include_path(fn)
  io = nil
  CDDL::cddl_include_path.each do |path|
    begin
      io = (path + fn).open
      break
    rescue Errno::ENOENT
      next
    end
  end
  io
end

.reason(parser, s) ⇒ Object 



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# File 'lib/cddlc.rb', line 16

def self.reason(parser, s)
  reason = [parser.failure_reason]
  parser.failure_reason =~ /^(Expected .+) after/m
  reason << "#{$1.gsub("\n", '<<<NEWLINE>>>')}:" if $1
  if line = s.lines.to_a[parser.failure_line - 1]
    reason << line
    reason << "#{'~' * (parser.failure_column - 1)}^"
  end
  reason.join("\n")
end

Instance Method Details

#cddl_add_used_by(prod, used) ⇒ Object 



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# File 'lib/processor/cddl-undefined.rb', line 21

def cddl_add_used_by(prod, used)
  cddl_extract_names(prod) do |name|
    used[name] = true
  end
end

#cddl_extract_names(prod, &name_used) ⇒ Object 



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# File 'lib/processor/cddl-undefined.rb', line 6

def cddl_extract_names(prod, &name_used)
  visit(prod) do |p|
    case p
      in ["gen", name, *_gen_args]
        name_used.call(name)
        false
      in ["name", name]
        name_used.call(name)
        false
      else
        false
    end
  end
end

#cddl_undefined ⇒ Object 



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# File 'lib/processor/cddl-undefined.rb', line 27

def cddl_undefined
  # currently only works on expanded...
  cddl2 = self.deep_clone                # needs deep-clone
  begin
    cddl2.expand_generics
  rescue CDDL::MissingGenericError => e
    return [e.name] # make this expandable first by pulling missing generic
  end
  used = {}
  cddl2.rules.each do |k, v|
    fail unless String === k
    cddl2.cddl_add_used_by(v, used)
  end
  used.keys.reject {|name| cddl2.rules[name] || prelude.rules[name]}
end

#constant_evaluate(rhs) ⇒ Object 



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# File 'lib/processor/cddl-constants.rb', line 5

def constant_evaluate(rhs)
  case rhs
  in ["number", n]
    [true, eval(n)]
  in ["text", n]
    [true, n]
  in ["name", n]
    if nv = rules[n]
      constant_evaluate(nv)
    end
  else
    [false]
  end
end

#deep_clone ⇒ Object 



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# File 'lib/cddlc.rb', line 224

def deep_clone
  Marshal.load(Marshal.dump(self))
end

#expand_generics ⇒ Object 



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# File 'lib/processor/cddl-expander.rb', line 46

def expand_generics
  @gen = {}
  rules.each do |name, prod|
    case prod
    in ["parm", parmnames, type]
      if prod[0] == "parm"
        @gen[name] = [parmnames, type]
      end
    else
    end
  end
  warn "@gen = #{@gen.inspect}" if $options.verbose
  @gen.each do |k, v|
    parmnames = v[0]
    fail unless rules[k] == ["parm", parmnames, v[1]]
    rules.delete(k)
  end
  @new_rules = {}
  rules.each do |name, prod|
    fail if Array === name
    @new_rules[name] = expand_prod(prod)
  end
  warn "@new_rules = #{@new_rules.inspect}" if $options.verbose
  @rules = @new_rules
end

#expand_prod(prod) ⇒ Object 



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# File 'lib/processor/cddl-expander.rb', line 36

def expand_prod(prod)
  visit(prod) do |p, &block|
    case p
    in ["gen", name, *gen_args]
      [true, gen_apply(name, gen_args, &block)]
    else
      [false]
    end
  end
end

#extract_constants ⇒ Object 



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# File 'lib/processor/cddl-constants.rb', line 19

def extract_constants
  nr = {}
  rules.each do |k, v|
    isconstant, value = constant_evaluate(v)
    nr[k] = value if isconstant
  end
  nr
end

#flattening ⇒ Object 



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# File 'lib/processor/cddl-flattening.rb', line 95

def flattening
  symtab = flattening_occurrences
  PP.pp(["*** SYMTAB", symtab], STDERR) if $options.verbose
  rules.replace(flattening_replace(symtab))
end

#flattening_key_name(key, value, env = nil) ⇒ Object 



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# File 'lib/processor/cddl-flattening.rb', line 6

def flattening_key_name(key, value, env = nil)
  case key
  in ["enum", ["mem", _cut, ["text", IDENTIFIER_RE => text], _]]
    [false, text]
  in ["text", IDENTIFIER_RE => text]
    [false, text]
  in ["number", INT_RE => intval] if env
    [true, "$.#{env}$#{intval}"]
  else
    [false]
  end
end

#flattening_mogrify(name, prod, symtab, alias_rules) ⇒ Object 



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# File 'lib/processor/cddl-flattening.rb', line 44

def flattening_mogrify(name, prod, symtab, alias_rules)
  step1 = visit(prod) do |here|
      case here
      in ["mem", cut, key, value]
        ### mogrify
        labeled, keyname = flattening_key_name(key, value, name)
        if keyname
          new_name =
            unless labeled
              syment = symtab[keyname]
              fail keyname unless Array === syment
              if syment.size == 1
                "$.#{keyname}"
              else
                "$.#{name}$#{keyname}"
              end
            else
              keyname
            end
          new_value2 = flattening_mogrify(new_name, value, symtab, alias_rules)
          new_name2 = new_name
          n = 0
          while ar = alias_rules[new_name2] and ar != new_value2
            n += 1
            new_name2 = new_name << "@" << n.to_s
          end
          alias_rules[new_name2] = new_value2
          [true, ["mem", cut, key, ["name", new_name2]]]
        end
      else
        false
      end
    end
  step2 = visit(step1) do |here|
    case here
    in ["enum", ["mem", _cut, ["text", IDENTIFIER_RE], ["name", MOGRIFIED_ID_RE => new_name2]]]
      [true, ["name", new_name2]]
    else
      false
    end
  end
  step2
end

#flattening_occurrences ⇒ Object 



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# File 'lib/processor/cddl-flattening.rb', line 18

def flattening_occurrences
  symtab = Hash.new { |h, k| h[k] = [] }
  rules.each do |name, prod|
    visit(prod) do |here|
      case here
      in ["mem", _cut, key, value]
        _labeled, keyname = flattening_key_name(key, value, false)
        if keyname
          symtab[keyname] << [name, value]
          false
        end
      else
        false
      end
    end
  end
  symtab_replacements = Hash[symtab.map do |k, v|
    s = Set[*v.map{_2}]
    # warn "** #{k} #{s.inspect}"
    if s.size == 1
      [k, [[v.map{|k, v| k}.join("|"), s.first]]]
    end
  end.compact]
  # warn "** symtab_replacements: #{symtab_replacements.inspect}" if $options.verbose
  symtab.merge(symtab_replacements)
end

#flattening_replace(symtab) ⇒ Object 



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# File 'lib/processor/cddl-flattening.rb', line 87

def flattening_replace(symtab)
  alias_rules = {}
  new_rules = Hash[rules.map do |name, prod|
                     [name,
                      flattening_mogrify(name, prod, symtab, alias_rules)]
                   end]
  new_rules.merge(alias_rules)
end

#gen_apply(gen_name, gen_args, &block) ⇒ Object 



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# File 'lib/processor/cddl-expander.rb', line 29

def gen_apply(gen_name, gen_args, &block)
  gen_parms, gen_prod = @gen[gen_name]
  unless gen_parms
    fail MissingGenericError.new(gen_name, gen_args)
  end
  substitute(gen_prod, gen_parms, gen_args, &block)
end

#perform_directives ⇒ Object 



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# File 'lib/cddlc.rb', line 78

def perform_directives
  directives.each do |di|
    preferred_tag = nil
    from = nil
    case di
    in [IMPINC => dir, SAFE_FN => docref, "as", SAFE_FN => preferred_tag]
    in [IMPINC => dir, SAFE_FN => docref]
    in [IMPINC => dir, *from, "from", SAFE_FN => docref, "as", SAFE_FN => preferred_tag]
    in [IMPINC => dir, *from, "from", SAFE_FN => docref]
    else
      warn "** Can't parse directive »#{di.join(" ")}«"
      next
    end
    if from
      from = from.map do |name|
        name.chomp!(",")
        if IDENTIFIER_RE === name
          name
        else
          warn "*** invalid identifier #{name.inspect} ignored in »#{di.join(' ')}«"
          nil
        end
      end.compact
    end
    warn "FROM #{from.inspect}" if $options.verbose
    warn "PREFERRED_TAG #{preferred_tag.inspect}" if $options.verbose
    warn "DOCREF #{docref.inspect}" if $options.verbose

    fn = docref.downcase << ".cddl"
    io = CDDL.read_from_include_path(fn)
    unless io
      warn "** #{dir} file #{fn} not found in #{CDDL::cddl_include_path.map(&:to_s)}"
      next
    end

    include_file = io.read
    included_cddl = CDDL.from_cddl(include_file)
    if preferred_tag
      included_cddl = included_cddl.deep_clone # needed?
      renamed_names = included_cddl.rules.keys
      name_rename = Hash[
        renamed_names.map { |o|
          n = "#{preferred_tag}.#{o}"
          warn "** Warning: renamed name #{n} already in #{fn}" if included_cddl.rules[n]
          [o, n]}]
      included_cddl.rename(name_rename)
    end

    case dir
    in "import"
      warn "** IMPORTING #{from && from.join(", ") << " from "}#{fn}" if $options.verbose

      must_be_found = false
      to_be_imported = if from
                         if preferred_tag
                           from.map{ |k|
                             if k =~ /\A#{preferred_tag}[.]/
                               k
                             elsif nn = name_rename[k]
                               if old = store_rule(k, v = ["name", nn])
                                 warn "*** autogenerated rule #{k} = #{v} would overwrite #{old}"
                               end
                               nn
                             else
                               warn_error "*** imported rule #{k.inspect} not in #{fn}"
                             end
                           }.compact
                         else
                           must_be_found = true
                           from
                         end
                       else
                         cddl_undefined
                       end
      loop do
        # p to_be_imported
        got_more = false
        to_be_imported.each do |name|
          if rule = included_cddl.rules[name]
            rules[name] = rule
            warn "IMPORTED #{name} from #{fn}" if $options.verbose
            got_more = true
          elsif must_be_found
            warn_error "*** imported rule #{name.inspect} not in #{fn}"
          end
        end
        break unless got_more
        recently_imported = to_be_imported
        to_be_imported = cddl_undefined # XXX square...
        warn "TO IMPORT #{to_be_imported.inspect}" if $options.verbose
        if to_be_imported == recently_imported
          fail "No progress importing #{to_be_imported.inspect} from #{fn} (generics issue?)"
        end
        must_be_found = false
      end
      if preferred_tag
        to_be_imported.each do |name|
          warn "** Warning: undefined reference #{name} without namespace prefix is defined in namespaced imported module #{fn}" if name_rename[name]
          ### instead just add rule...
        end
      end
    in "include"
      if from
        from = Set[*from]
      end
      warn "** INCLUDING #{from && from.join(", ") << " from "}#{fn}" if $options.verbose
      included_cddl.rules.each do |k, v|
        if from
          next unless from.include?(k)
          from.delete(k)
        end
        if old = store_rule(k, v)
          warn "*** included rule #{k} = #{v} would overwrite #{old}"
        end
      end
      if from && !from.empty?
        warn "*** could not find #{from.join(", ")} in #{fn}"
      end
    end
  end
end

#prec_check(inner, targetprec, prec, indent_s) ⇒ Object

precedence: 0: // gcho 1: , seq 2: / tcho -> (type1) 3: (type1) .xxx op -> type2 4: type2



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# File 'lib/writer/cddl-writer.rb', line 20

def prec_check(inner, targetprec, prec, indent_s)
  if targetprec > prec
    "(#{inner.gsub("\n", "\n" << indent_s)})" # XXX embedded byte strings
  else
    inner
  end
end

#prelude ⇒ Object 



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# File 'lib/cddlc.rb', line 278

def prelude
  if @prelude.nil?
    @prelude = CDDL.from_cddl(File.read(DATA_DIR + "prelude.cddl"))

  end
  @prelude
end

#rename(rename_map) ⇒ Object

(keeps only renamed rules)



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# File 'lib/cddlc.rb', line 28

def rename(rename_map)
  rules.replace(
    Hash[rename_map.map do |o, n|
           [n, visit(rules[o]) do |prod|
              case prod
              in ["name", *] | ["gen", *]
                prod[1] = rename_map[prod[1]] || prod[1]
              else
              end
              false
            end]
         end])
end

#rules ⇒ Object 



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# File 'lib/cddlc.rb', line 231

def rules
  if @rules.nil?              # memoize
    @rules = {}
    fail unless @tree.first == "cddl"
    @tree[1..-1].each do |x|
      op, name, val, rest = x
      cho = RULE_OP_TO_CHOICE[op]
      fail rest if rest
      fail name unless Array === name
      case name[0]
      when "name"
        fail unless name.size == 2
        name = name[1]
      when "gen"
        parmnames = name[2..-1]
        name = name[1]        # XXX update val with parm/arg
        val = ["parm", parmnames,
               visit(val) do |p|
                 case p
                 in ["name", nm]
                   if ix = parmnames.index(nm)
                     [true, ["arg", ix]]
                   end
                 else
                   false
                 end
               end]
      else
        fail name
      end
      @rules[name] =
        if (old = @rules[name]) && old != val
          fail "duplicate rule for name #{name} #{old.inspect} #{val.inspect}" unless cho
          if Array === old && old[0] == cho
            old.dup << val
          else
            [cho, old, val]
          end
        else
          val
        end
    end
    # warn "** rules #{rules.inspect}"
  end
  @rules
end

#store_rule(k, v) ⇒ Object 



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# File 'lib/cddlc.rb', line 200

def store_rule(k, v)
  if old = rules[k]
    if old != v
      return old              # error
    end
  else
    rules[k] = v
  end
  nil                         # OK
end

#substitute(prod, parms, subs, &block) ⇒ Object 



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# File 'lib/processor/cddl-expander.rb', line 15

def substitute(prod, parms, subs, &block)
  visit(prod) do |p, &block1|
    case p
    in ["gen", name, *gen_args] # XXX
      [true, gen_apply(name, gen_args, &block1)]
    in ["arg", num]
      if replacement = subs[num]
        [true, visit(expand_prod(replacement), &block)]
      end
    else
      false
    end
  end
end

#to_s ⇒ Object 



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# File 'lib/writer/cddl-writer.rb', line 112

def to_s
  rules.map {|k, v|
    parmnames = false
    case v
    in ["parm", parmnames, _type]
    else
    end
    "#{write_lhs(k, parmnames)} = #{write_rhs(v, 2.1)}" # 2: parenthesize groups
  }.join("\n")
end

#visit(prod, &block) ⇒ Object 



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# File 'lib/processor/cddl-visitor.rb', line 7

def visit(prod, &block)
  done, ret = block.call(prod, &block)
  if done
    return ret
  end

  case prod
  in ["parm", parmnames, prod]
    ["parm", parmnames, visit(prod, &block)]
  in ["gen", name, *types]
    ["gen", name, *visit_all(types, &block)]
  in ["op", op, *prods]
    ["op", op, *visit_all(prods, &block)]
  in ["map", prod]
    ["map", visit(prod, &block)]
  in ["ary", prod]
    ["ary", visit(prod, &block)]
  in ["gcho", *prods]
    ["gcho", *visit_all(prods, &block)]
  in ["tcho", *prods]
    ["tcho", *visit_all(prods, &block)]
  in ["seq", *prods]
    ["seq", *visit_all(prods, &block)]
  in ["enum", prod]
    ["enum", visit(prod, &block)]
  in ["unwrap", prod]
    ["unwrap", visit(prod, &block)] # XXX, this may need to be bottled in a rule
  in ["prim", prod, *prods]
    ["prim", visit(prod, &block), *visit_all(prods, &block)]
  in ["mem", cut, *prods]
    ["mem", cut, *visit_all(prods, &block)]
  in ["rep", s, e, prod]
    ["rep", s, e, visit(prod, &block)]
  else
    prod
  end
end

#visit_all(prod_array, &block) ⇒ Object 



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# File 'lib/processor/cddl-visitor.rb', line 4

def visit_all(prod_array, &block)
  prod_array.map {|prod| visit(prod, &block)}
end

#warn_error(s) ⇒ Object 



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# File 'lib/cddlc.rb', line 211

def warn_error(s)
  warn s
  @error = true
end

#write_lhs(k, parmnames) ⇒ Object 



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# File 'lib/writer/cddl-writer.rb', line 5

def write_lhs(k, parmnames)
  if parmnames
    "#{k}<#{parmnames.join(", ")}>"
  else
    k
  end
end

#write_rhs(v, targetprec = 0, indent = 0, pn = []) ⇒ Object 



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# File 'lib/writer/cddl-writer.rb', line 28

def write_rhs(v, targetprec = 0, indent = 0, pn = [])
  # pn = parmnames
#    warn "** #{v.inspect}"
  indent_p = "  " * indent
  indent += 1
  indent_s = "  " * indent
  prec, ret =
  case v
  in ["parm", parmnames, type]
    [4, write_rhs(type, 2, indent, parmnames)]
  in ["arg", Integer => num]
    [4, pn[num] || "id$#{num}"]
  in ["name", id]
    [4, id]
  in ["gen", id, *parms]  # oops -- namep vs. namea; ouch
    [4, "#{id}<#{parms.map{write_rhs(_1, 2, indent, pn)}.join(", ")}>"]
  in ["tcho", *types]
    [2.1, types.map{write_rhs(_1, 3, indent, pn)}.join(" / ")]
  in ["gcho", *groups]
    [0, groups.map{write_rhs(_1, 2, indent, pn)}.join(" // ")]
  in ["op", op, l, r]
    [3, "#{write_rhs(l, 4, indent, pn)} #{op} #{write_rhs(r, 4, indent, pn)}"]
    # 3->4: work around cddl tool limitation
  in ["map", group]
    [3, "{#{write_rhs(group, 0, indent, pn)}}"] # 4->3: work around cddl tool limitation
  in ["ary", group]
    [3, "[#{write_rhs(group, 0, indent, pn)}]"] # 4->3: work around cddl tool limitation
  in ["unwrap", namep]
    [4, "~#{write_rhs(namep, 4, indent, pn)}"]
  in ["enum", ["name", _name] => namep]
    [4, "&#{write_rhs(namep, 4, indent, pn)}"]
  in ["enum", ["gen", _name, *types] => namep]
    [4, "&#{write_rhs(namep, 4, indent, pn)})"]
  in ["enum", group]
    [4, "&(#{write_rhs(group, 0, indent, pn)})"]
  in ["prim"]
    [4, "#"]
  in ["prim", maj]
    [4, "##{maj}"]
  in ["prim", maj, min]
    [4, "##{maj}.#{min}"]
  in ["prim", 6, Integer => tag, type]
    [4, "#6.#{tag}(#{write_rhs(type, 0, indent, pn)})"]
  in ["prim", 6, Array => tag, type]
    [4, "#6.<#{write_rhs(tag, 0, indent, pn)}>(#{write_rhs(type, 0, indent, pn)})"]
  in ["prim", 6, nil, type]
    [4, "#6(#{write_rhs(type, 0, indent, pn)})"]
# prim: extension for #6.<i>(t)
  in ["seq", *groups]
    case groups.size
    when 0; [4, ""]
    # when 1; "#{write_rhs(g[0], targetprec, indent, pn)}"
    else
      [1, "\n#{indent_p}#{groups.map{write_rhs(_1, 1, indent, pn)}.join(",\n#{indent_p}")},\n"]
    end
  in ["rep", s, e, group]
    occur = case [s, e]
            in [1, 1];     ""
            in [0, 1];     "? "
            in [0, false]; "* "
            in [1, false]; "+ "
            else
              "#{s}*#{e || ""}"
            end
    [1, "#{occur}#{write_rhs(group, 2, indent, pn)}"]
  in ["mem", false, nil, t2]
    [2, write_rhs(t2, 2, indent, pn)]
  in ["mem", true, ["text", IDENTIFIER_RE => bareword], t2]
    [2, "#{bareword}: #{write_rhs(t2, 2, indent, pn)}"]
  in ["mem", true, ["number", INT_RE => bareword], t2]
    [2, "#{bareword}: #{write_rhs(t2, 2, indent, pn)}"]
  in ["mem", cut, t1, t2]
    [2, "#{write_rhs(t1, 3, indent, pn)} #{cut ? "^" : ""}=> #{write_rhs(t2, 2, indent, pn)}"]
    # 2->3: work around cddl tool limitation
  in ["bytes", t]
    [4, t]                    # XXX not very clean
  in ["text", t]
    [4, "\"#{t}\""]           # XXX escape
  in ["number", t]
    [4, t.to_s]
  end
  prec_check(ret, targetprec, prec, indent_s)
end