Class: Ruby2Ruby

Inherits:
SexpProcessor
  • Object
show all
Defined in:
lib/ruby2ruby.rb

Overview

Generate ruby code from a sexp.

Constant Summary collapse

VERSION =

:nodoc:

"2.0.6"
LINE_LENGTH =

cutoff for one-liners

78
BINARY =

binary operation messages

[:<=>, :==, :<, :>, :<=, :>=, :-, :+, :*, :/, :%, :<<, :>>, :**]
ASSIGN_NODES =

Nodes that represent assignment and probably need () around them.

TODO: this should be replaced with full precedence support :/

[
 :dasgn,
 :flip2,
 :flip3,
 :lasgn,
 :masgn,
 :attrasgn,
 :op_asgn1,
 :op_asgn2,
 :op_asgn_and,
 :op_asgn_or,
 :return,
 :if, # HACK
]

Instance Method Summary collapse

Constructor Details

#initialize ⇒ Ruby2Ruby

:nodoc:



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# File 'lib/ruby2ruby.rb', line 60

def initialize # :nodoc:
  super
  @indent = "  "
  self.auto_shift_type = true
  self.strict = true
  self.expected = String

  @calls = []

  # self.debug[:defn] = /zsuper/
end

Instance Method Details

#cond_loop(exp, name) ⇒ Object

Generate a post-or-pre conditional loop.



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# File 'lib/ruby2ruby.rb', line 939

def cond_loop(exp, name)
  cond = process(exp.shift)
  body = process(exp.shift)
  head_controlled = exp.shift

  body = indent(body).chomp if body

  code = []
  if head_controlled then
    code << "#{name} #{cond} do"
    code << body if body
    code << "end"
  else
    code << "begin"
    code << body if body
    code << "end #{name} #{cond}"
  end
  code.join("\n")
end

#dthing_escape(type, lit) ⇒ Object

Utility method to escape something interpolated.



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# File 'lib/ruby2ruby.rb', line 962

def dthing_escape type, lit
  lit = lit.gsub(/\n/, '\n')
  case type
  when :dregx then
    lit.gsub(/(\A|[^\\])\//, '\1\/')
  when :dstr, :dsym then
    lit.gsub(/"/, '\"')
  when :dxstr then
    lit.gsub(/`/, '\`')
  else
    raise "unsupported type #{type.inspect}"
  end
end

#finish(exp) ⇒ Object

Process all the remaining stuff in exp and return the results sans-nils.



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# File 'lib/ruby2ruby.rb', line 980

def finish exp # REFACTOR: work this out of the rest of the processors
  body = []
  until exp.empty? do
    body << process(exp.shift)
  end
  body.compact
end

#indent(s) ⇒ Object

Indent all lines of s to the current indent level.



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# File 'lib/ruby2ruby.rb', line 991

def indent(s)
  s.to_s.split(/\n/).map{|line| @indent + line}.join("\n")
end

#parenthesize(exp) ⇒ Object

Wrap appropriate expressions in matching parens.



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# File 'lib/ruby2ruby.rb', line 998

def parenthesize exp
  case self.context[1]
  when nil, :defn, :defs, :class, :sclass, :if, :iter, :resbody, :when, :while then
    exp
  else
    "(#{exp})"
  end
end

#process_alias(exp) ⇒ Object

Processors



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# File 'lib/ruby2ruby.rb', line 75

def process_alias(exp) # :nodoc:
  parenthesize "alias #{process(exp.shift)} #{process(exp.shift)}"
end

#process_and(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 79

def process_and(exp) # :nodoc:
  parenthesize "#{process exp.shift} and #{process exp.shift}"
end

#process_arglist(exp) ⇒ Object

custom made node # :nodoc:



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# File 'lib/ruby2ruby.rb', line 83

def process_arglist(exp) # custom made node # :nodoc:
  code = []
  until exp.empty? do
    code << process(exp.shift)
  end
  code.join ', '
end

#process_args(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 91

def process_args(exp) # :nodoc:
  args = []

  until exp.empty? do
    arg = exp.shift
    case arg
    when Symbol then
      args << arg
    when Sexp then
      case arg.first
      when :lasgn then
        args << process(arg)
      else
        raise "unknown arg type #{arg.first.inspect}"
      end
    else
      raise "unknown arg type #{arg.inspect}"
    end
  end

  "(#{args.join ', '})"
end

#process_array(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 114

def process_array(exp) # :nodoc:
  "[#{process_arglist(exp)}]"
end

#process_attrasgn(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 118

def process_attrasgn(exp) # :nodoc:
  receiver = process exp.shift
  name = exp.shift
  rhs  = exp.pop
  args = s(:array, *exp)
  exp.clear

  case name
  when :[]= then
    args = process args
    "#{receiver}#{args} = #{process rhs}"
  else
    raise "dunno what to do: #{args.inspect}" unless args.size == 1 # s(:array)
    name = name.to_s.sub(/=$/, '')
    if rhs && rhs != s(:arglist) then
      "#{receiver}.#{name} = #{process(rhs)}"
    else
      raise "dunno what to do: #{rhs.inspect}"
    end
  end
end

#process_back_ref(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 140

def process_back_ref(exp) # :nodoc:
  "$#{exp.shift}"
end

#process_begin(exp) ⇒ Object

TODO: figure out how to do rescue and ensure ENTIRELY w/o begin



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# File 'lib/ruby2ruby.rb', line 145

def process_begin(exp) # :nodoc:
  code = []
  code << "begin"
  until exp.empty?
    src = process(exp.shift)
    src = indent(src) unless src =~ /(^|\n)(rescue|ensure)/ # ensure no level 0 rescues
    code << src
  end
  code << "end"
  return code.join("\n")
end

#process_block(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 157

def process_block(exp) # :nodoc:
  result = []

  exp << nil if exp.empty?
  until exp.empty? do
    code = exp.shift
    if code.nil? or code.first == :nil then
      result << "# do nothing\n"
    else
      result << process(code)
    end
  end

  result = parenthesize result.join "\n"
  result += "\n" unless result.start_with? "("

  return result
end

#process_block_pass(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 176

def process_block_pass exp # :nodoc:
  raise "huh?: #{exp.inspect}" if exp.size > 1

  "&#{process exp.shift}"
end

#process_break(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 182

def process_break(exp) # :nodoc:
  val = exp.empty? ? nil : process(exp.shift)
  # HACK "break" + (val ? " #{val}" : "")
  if val then
    "break #{val}"
  else
    "break"
  end
end

#process_call(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 192

def process_call(exp) # :nodoc:
  receiver_node_type = exp.first.nil? ? nil : exp.first.first
  receiver = process exp.shift
  receiver = "(#{receiver})" if ASSIGN_NODES.include? receiver_node_type

  name = exp.shift
  args = []

  # this allows us to do both old and new sexp forms:
  exp.push(*exp.pop[1..-1]) if exp.size == 1 && exp.first.first == :arglist

  @calls.push name

  in_context :arglist do
    until exp.empty? do
      arg_type = exp.first.sexp_type
      is_empty_hash = (exp.first == s(:hash))
      arg = process exp.shift

      next if arg.empty?

      strip_hash = (arg_type == :hash and
                    not BINARY.include? name and
                    not is_empty_hash and
                    (exp.empty? or exp.first.sexp_type == :splat))
      wrap_arg = Ruby2Ruby::ASSIGN_NODES.include? arg_type

      arg = arg[2..-3] if strip_hash
      arg = "(#{arg})" if wrap_arg

      args << arg
    end
  end

  case name
  when *BINARY then
    "(#{receiver} #{name} #{args.join(', ')})"
  when :[] then
    receiver ||= "self"
    "#{receiver}[#{args.join(', ')}]"
  when :[]= then
    receiver ||= "self"
    rhs = args.pop
    "#{receiver}[#{args.join(', ')}] = #{rhs}"
  when :"!" then
    "(not #{receiver})"
  when :"-@" then
    "-#{receiver}"
  when :"+@" then
    "+#{receiver}"
  else
    args     = nil                    if args.empty?
    args     = "(#{args.join(', ')})" if args
    receiver = "#{receiver}."         if receiver

    "#{receiver}#{name}#{args}"
  end
ensure
  @calls.pop
end

#process_case(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 253

def process_case(exp) # :nodoc:
  result = []
  expr = process exp.shift
  if expr then
    result << "case #{expr}"
  else
    result << "case"
  end
  until exp.empty?
    pt = exp.shift
    if pt and pt.first == :when
      result << "#{process(pt)}"
    else
      code = indent(process(pt))
      code = indent("# do nothing") if code =~ /^\s*$/
      result << "else\n#{code}"
    end
  end
  result << "end"
  result.join("\n")
end

#process_cdecl(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 275

def process_cdecl(exp) # :nodoc:
  lhs = exp.shift
  lhs = process lhs if Sexp === lhs
  unless exp.empty? then
    rhs = process(exp.shift)
    "#{lhs} = #{rhs}"
  else
    lhs.to_s
  end
end

#process_class(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 286

def process_class(exp) # :nodoc:
  "#{exp.comments}class #{util_module_or_class(exp, true)}"
end

#process_colon2(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 290

def process_colon2(exp) # :nodoc:
  "#{process(exp.shift)}::#{exp.shift}"
end

#process_colon3(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 294

def process_colon3(exp) # :nodoc:
  "::#{exp.shift}"
end

#process_const(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 298

def process_const(exp) # :nodoc:
  exp.shift.to_s
end

#process_cvar(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 302

def process_cvar(exp) # :nodoc:
  "#{exp.shift}"
end

#process_cvasgn(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 306

def process_cvasgn(exp) # :nodoc:
  "#{exp.shift} = #{process(exp.shift)}"
end

#process_cvdecl(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 310

def process_cvdecl(exp) # :nodoc:
  "#{exp.shift} = #{process(exp.shift)}"
end

#process_defined(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 314

def process_defined(exp) # :nodoc:
  "defined? #{process(exp.shift)}"
end

#process_defn(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 318

def process_defn(exp) # :nodoc:
  type1 = exp[1].first
  type2 = exp[2].first rescue nil
  expect = [:ivar, :iasgn, :attrset]

  # s(name, args, ivar|iasgn|attrset)
  if exp.size == 3 and type1 == :args and expect.include? type2 then
    name = exp.first # don't shift in case we pass through
    case type2
    when :ivar then
      ivar_name = exp.ivar.last

      meth_name = ivar_name.to_s[1..-1].to_sym
      expected = s(meth_name, s(:args), s(:ivar, ivar_name))

      if exp == expected then
        exp.clear
        return "attr_reader #{name.inspect}"
      end
    when :attrset then
      # TODO: deprecate? this is a PT relic
      exp.clear
      return "attr_writer :#{name.to_s[0..-2]}"
    when :iasgn then
      ivar_name = exp.iasgn[1]
      meth_name = "#{ivar_name.to_s[1..-1]}=".to_sym
      arg_name = exp.args.last
      expected = s(meth_name, s(:args, arg_name),
                   s(:iasgn, ivar_name, s(:lvar, arg_name)))

      if exp == expected then
        exp.clear
        return "attr_writer :#{name.to_s[0..-2]}"
      end
    else
      raise "Unknown defn type: #{exp.inspect}"
    end
  end

  comm = exp.comments
  name = exp.shift
  args = process exp.shift
  args = "" if args == "()"

  exp.shift if exp == s(s(:nil)) # empty it out of a default nil expression

  # REFACTOR: use process_block but get it happier wrt parenthesize
  body = []
  until exp.empty? do
    body << indent(process(exp.shift))
  end

  body << indent("# do nothing") if body.empty?

  body = body.join("\n")

  return "#{comm}def #{name}#{args}\n#{body}\nend".gsub(/\n\s*\n+/, "\n")
end

#process_defs(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 377

def process_defs(exp) # :nodoc:
  lhs  = exp.shift
  var = [:self, :cvar, :dvar, :ivar, :gvar, :lvar].include? lhs.first
  name = exp.shift

  lhs = process(lhs)
  lhs = "(#{lhs})" unless var

  exp.unshift "#{lhs}.#{name}"
  process_defn(exp)
end

#process_dot2(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 389

def process_dot2(exp) # :nodoc:
  "(#{process exp.shift}..#{process exp.shift})"
end

#process_dot3(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 393

def process_dot3(exp) # :nodoc:
  "(#{process exp.shift}...#{process exp.shift})"
end

#process_dregx(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 397

def process_dregx(exp) # :nodoc:
  options = re_opt exp.pop if Fixnum === exp.last
  "/" << util_dthing(:dregx, exp) << "/#{options}"
end

#process_dregx_once(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 402

def process_dregx_once(exp) # :nodoc:
  process_dregx(exp) + "o"
end

#process_dstr(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 406

def process_dstr(exp) # :nodoc:
  "\"#{util_dthing(:dstr, exp)}\""
end

#process_dsym(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 410

def process_dsym(exp) # :nodoc:
  ":\"#{util_dthing(:dsym, exp)}\""
end

#process_dxstr(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 414

def process_dxstr(exp) # :nodoc:
  "`#{util_dthing(:dxstr, exp)}`"
end

#process_ensure(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 418

def process_ensure(exp) # :nodoc:
  body = process exp.shift
  ens  = exp.shift
  ens  = nil if ens == s(:nil)
  ens  = process(ens) || "# do nothing"
  ens = "begin\n#{ens}\nend\n" if ens =~ /(^|\n)rescue/

  body.sub!(/\n\s*end\z/, '')
  body = indent(body) unless body =~ /(^|\n)rescue/

  return "#{body}\nensure\n#{indent ens}"
end

#process_evstr(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 431

def process_evstr(exp) # :nodoc:
  exp.empty? ? '' : process(exp.shift)
end

#process_false(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 435

def process_false(exp) # :nodoc:
  "false"
end

#process_flip2(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 439

def process_flip2(exp) # :nodoc:
  "#{process(exp.shift)}..#{process(exp.shift)}"
end

#process_flip3(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 443

def process_flip3(exp) # :nodoc:
  "#{process(exp.shift)}...#{process(exp.shift)}"
end

#process_for(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 447

def process_for(exp) # :nodoc:
  recv = process exp.shift
  iter = process exp.shift
  body = exp.empty? ? nil : process(exp.shift)

  result = ["for #{iter} in #{recv} do"]
  result << indent(body ? body : "# do nothing")
  result << "end"

  result.join("\n")
end

#process_gasgn(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 459

def process_gasgn(exp) # :nodoc:
  process_iasgn(exp)
end

#process_gvar(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 463

def process_gvar(exp) # :nodoc:
  return exp.shift.to_s
end

#process_hash(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 467

def process_hash(exp) # :nodoc:
  result = []

  until exp.empty?
    lhs = process(exp.shift)
    rhs = exp.shift
    t = rhs.first
    rhs = process rhs
    rhs = "(#{rhs})" unless [:lit, :str].include? t # TODO: verify better!

    result << "#{lhs} => #{rhs}"
  end

  return result.empty? ? "{}" : "{ #{result.join(', ')} }"
end

#process_iasgn(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 483

def process_iasgn(exp) # :nodoc:
  lhs = exp.shift
  if exp.empty? then # part of an masgn
    lhs.to_s
  else
    "#{lhs} = #{process exp.shift}"
  end
end

#process_if(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 492

def process_if(exp) # :nodoc:
  expand = Ruby2Ruby::ASSIGN_NODES.include? exp.first.first
  c = process exp.shift
  t = process exp.shift
  f = process exp.shift

  c = "(#{c.chomp})" if c =~ /\n/

  if t then
    unless expand then
      if f then
        r = "#{c} ? (#{t}) : (#{f})"
        r = nil if r =~ /return/ # HACK - need contextual awareness or something
      else
        r = "#{t} if #{c}"
      end
      return r if r and (@indent+r).size < LINE_LENGTH and r !~ /\n/
    end

    r = "if #{c} then\n#{indent(t)}\n"
    r << "else\n#{indent(f)}\n" if f
    r << "end"

    r
  elsif f
    unless expand then
      r = "#{f} unless #{c}"
      return r if (@indent+r).size < LINE_LENGTH and r !~ /\n/
    end
    "unless #{c} then\n#{indent(f)}\nend"
  else
    # empty if statement, just do it in case of side effects from condition
    "if #{c} then\n#{indent '# do nothing'}\nend"
  end
end

#process_iter(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 528

def process_iter(exp) # :nodoc:
  iter = process exp.shift
  args = exp.shift
  body = exp.empty? ? nil : process(exp.shift)

  args = case args
         when 0 then
           " ||"
         else
           a = process(args)[1..-2]
           a = " |#{a}|" unless a.empty?
           a
         end

  b, e = if iter == "END" then
           [ "{", "}" ]
         else
           [ "do", "end" ]
         end

  iter.sub!(/\(\)$/, '')

  # REFACTOR: ugh
  result = []
  result << "#{iter} {"
  result << args
  if body then
    result << " #{body.strip} "
  else
    result << ' '
  end
  result << "}"
  result = result.join
  return result if result !~ /\n/ and result.size < LINE_LENGTH

  result = []
  result << "#{iter} #{b}"
  result << args
  result << "\n"
  if body then
    result << indent(body.strip)
    result << "\n"
  end
  result << e
  result.join
end

#process_ivar(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 575

def process_ivar(exp) # :nodoc:
  exp.shift.to_s
end

#process_lasgn(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 579

def process_lasgn(exp) # :nodoc:
  s = "#{exp.shift}"
  s += " = #{process exp.shift}" unless exp.empty?
  s
end

#process_lit(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 585

def process_lit(exp) # :nodoc:
  obj = exp.shift
  case obj
  when Range then
    "(#{obj.inspect})"
  else
    obj.inspect
  end
end

#process_lvar(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 595

def process_lvar(exp) # :nodoc:
  exp.shift.to_s
end

#process_masgn(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 599

def process_masgn(exp) # :nodoc:
  lhs = exp.shift
  rhs = exp.empty? ? nil : exp.shift

  case lhs.first
  when :array then
    lhs.shift
    lhs = lhs.map do |l|
      case l.first
      when :masgn then
        "(#{process(l)})"
      else
        process(l)
      end
    end
  when :lasgn then
    lhs = [ splat(lhs.last) ]
  when :splat then
    lhs = [ :"*" ]
  else
    raise "no clue: #{lhs.inspect}"
  end

  if context[1] == :iter and rhs then
    lhs << splat(rhs[1])
    rhs = nil
  end

  unless rhs.nil? then
    t = rhs.first
    rhs = process rhs
    rhs = rhs[1..-2] if t == :array # FIX: bad? I dunno
    return "#{lhs.join(", ")} = #{rhs}"
  else
    return lhs.join(", ")
  end
end

#process_match(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 637

def process_match(exp) # :nodoc:
  "#{process(exp.shift)}"
end

#process_match2(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 641

def process_match2(exp) # :nodoc:
  lhs = process(exp.shift)
  rhs = process(exp.shift)
  "#{lhs} =~ #{rhs}"
end

#process_match3(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 647

def process_match3(exp) # :nodoc:
  rhs = process(exp.shift)
  left_type = exp.first.sexp_type
  lhs = process(exp.shift)

  if ASSIGN_NODES.include? left_type then
    "(#{lhs}) =~ #{rhs}"
  else
    "#{lhs} =~ #{rhs}"
  end
end

#process_module(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 659

def process_module(exp) # :nodoc:
  "#{exp.comments}module #{util_module_or_class(exp)}"
end

#process_next(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 663

def process_next(exp) # :nodoc:
  val = exp.empty? ? nil : process(exp.shift)
  if val then
    "next #{val}"
  else
    "next"
  end
end

#process_nil(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 672

def process_nil(exp) # :nodoc:
  "nil"
end

#process_not(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 676

def process_not(exp) # :nodoc:
  "(not #{process exp.shift})"
end

#process_nth_ref(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 680

def process_nth_ref(exp) # :nodoc:
  "$#{exp.shift}"
end

#process_op_asgn1(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 684

def process_op_asgn1(exp) # :nodoc:
  # [[:lvar, :b], [:arglist, [:lit, 1]], :"||", [:lit, 10]]
  lhs = process(exp.shift)
  index = process(exp.shift)
  msg = exp.shift
  rhs = process(exp.shift)

  "#{lhs}[#{index}] #{msg}= #{rhs}"
end

#process_op_asgn2(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 694

def process_op_asgn2(exp) # :nodoc:
  # [[:lvar, :c], :var=, :"||", [:lit, 20]]
  lhs = process(exp.shift)
  index = exp.shift.to_s[0..-2]
  msg = exp.shift

  rhs = process(exp.shift)

  "#{lhs}.#{index} #{msg}= #{rhs}"
end

#process_op_asgn_and(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 705

def process_op_asgn_and(exp) # :nodoc:
  # a &&= 1
  # [[:lvar, :a], [:lasgn, :a, [:lit, 1]]]
  exp.shift
  process(exp.shift).sub(/\=/, '&&=')
end

#process_op_asgn_or(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 712

def process_op_asgn_or(exp) # :nodoc:
  # a ||= 1
  # [[:lvar, :a], [:lasgn, :a, [:lit, 1]]]
  exp.shift
  process(exp.shift).sub(/\=/, '||=')
end

#process_or(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 719

def process_or(exp) # :nodoc:
  "(#{process exp.shift} or #{process exp.shift})"
end

#process_postexe(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 723

def process_postexe(exp) # :nodoc:
  "END"
end

#process_redo(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 727

def process_redo(exp) # :nodoc:
  "redo"
end

#process_resbody(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 731

def process_resbody exp # :nodoc:
  args = exp.shift
  body = finish(exp)
  body << "# do nothing" if body.empty?

  name =   args.lasgn true
  name ||= args.iasgn true
  args = process(args)[1..-2]
  args = " #{args}" unless args.empty?
  args += " => #{name[1]}" if name

  "rescue#{args}\n#{indent body.join("\n")}"
end

#process_rescue(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 745

def process_rescue exp # :nodoc:
  body = process(exp.shift) unless exp.first.first == :resbody
  els  = process(exp.pop)   unless exp.last.first  == :resbody

  body ||= "# do nothing"
  simple = exp.size == 1 && !exp.resbody.block && exp.resbody.size <= 3

  resbodies = []
  until exp.empty? do
    resbody = exp.shift
    simple &&= resbody[1] == s(:array)
    simple &&= resbody[2] != nil && resbody[2].node_type != :block
    resbodies << process(resbody)
  end

  if els then
    "#{indent body}\n#{resbodies.join("\n")}\nelse\n#{indent els}"
  elsif simple then
    resbody = resbodies.first.sub(/\n\s*/, ' ')
    "#{body} #{resbody}"
  else
    "#{indent body}\n#{resbodies.join("\n")}"
  end
end

#process_retry(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 770

def process_retry(exp) # :nodoc:
  "retry"
end

#process_return(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 774

def process_return(exp) # :nodoc:
  # HACK return "return" + (exp.empty? ? "" : " #{process exp.shift}")

  if exp.empty? then
    return "return"
  else
    return "return #{process exp.shift}"
  end
end

#process_sclass(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 784

def process_sclass(exp) # :nodoc:
  "class << #{process(exp.shift)}\n#{indent(process_block(exp))}\nend"
end

#process_self(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 788

def process_self(exp) # :nodoc:
  "self"
end

#process_splat(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 792

def process_splat(exp) # :nodoc:
  if exp.empty? then
    "*"
  else
    "*#{process(exp.shift)}"
  end
end

#process_str(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 800

def process_str(exp) # :nodoc:
  return exp.shift.dump
end

#process_super(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 804

def process_super(exp) # :nodoc:
  args = finish exp

  "super(#{args.join(', ')})"
end

#process_svalue(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 810

def process_svalue(exp) # :nodoc:
  code = []
  until exp.empty? do
    code << process(exp.shift)
  end
  code.join(", ")
end

#process_to_ary(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 818

def process_to_ary(exp) # :nodoc:
  process(exp.shift)
end

#process_true(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 822

def process_true(exp) # :nodoc:
  "true"
end

#process_undef(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 826

def process_undef(exp) # :nodoc:
  "undef #{process(exp.shift)}"
end

#process_until(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 830

def process_until(exp) # :nodoc:
  cond_loop(exp, 'until')
end

#process_valias(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 834

def process_valias(exp) # :nodoc:
  "alias #{exp.shift} #{exp.shift}"
end

#process_when(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 838

def process_when(exp) # :nodoc:
  src = []

  if self.context[1] == :array then # ugh. matz! why not an argscat?!?
    val = process(exp.shift)
    exp.shift # empty body
    return "*#{val}"
  end

  until exp.empty?
    cond = process(exp.shift).to_s[1..-2]
    code = indent(finish(exp).join("\n"))
    code = indent "# do nothing" if code =~ /\A\s*\Z/
    src << "when #{cond} then\n#{code.chomp}"
  end

  src.join("\n")
end

#process_while(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 857

def process_while(exp) # :nodoc:
  cond_loop(exp, 'while')
end

#process_xstr(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 861

def process_xstr(exp) # :nodoc:
  "`#{process_str(exp)[1..-2]}`"
end

#process_yield(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 865

def process_yield(exp) # :nodoc:
  args = []
  until exp.empty? do
    args << process(exp.shift)
  end

  unless args.empty? then
    "yield(#{args.join(', ')})"
  else
    "yield"
  end
end

#process_zsuper(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 878

def process_zsuper(exp) # :nodoc:
  "super"
end

#re_opt(options) ⇒ Object

Return the appropriate regexp flags for a given numeric code.



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# File 'lib/ruby2ruby.rb', line 1010

def re_opt options
  bits = (0..8).map { |n| options[n] * 2**n }
  bits.delete 0
  bits.map { |n| Regexp::CODES[n] }.join
end

#rewrite_attrasgn(exp) ⇒ Object

Rewriters:



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# File 'lib/ruby2ruby.rb', line 885

def rewrite_attrasgn exp # :nodoc:
  if context.first(2) == [:array, :masgn] then
    exp[0] = :call
    exp[2] = exp[2].to_s.sub(/=$/, '').to_sym
  end

  exp
end

#rewrite_ensure(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 894

def rewrite_ensure exp # :nodoc:
  exp = s(:begin, exp) unless context.first == :begin
  exp
end

#rewrite_resbody(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 899

def rewrite_resbody exp # :nodoc:
  raise "no exception list in #{exp.inspect}" unless exp.size > 2 && exp[1]
  raise exp[1].inspect if exp[1][0] != :array
  # for now, do nothing, just check and freak if we see an errant structure
  exp
end

#rewrite_rescue(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 906

def rewrite_rescue exp # :nodoc:
  complex = false
  complex ||= exp.size > 3
  complex ||= exp.resbody.block
  complex ||= exp.resbody.size > 3
  complex ||= exp.find_nodes(:resbody).any? { |n| n[1] != s(:array) }
  complex ||= exp.find_nodes(:resbody).any? { |n| n.last.nil? }
  complex ||= exp.find_nodes(:resbody).any? { |n| n[2] and n[2].node_type == :block }

  handled = context.first == :ensure

  exp = s(:begin, exp) if complex unless handled

  exp
end

#rewrite_svalue(exp) ⇒ Object

:nodoc:



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# File 'lib/ruby2ruby.rb', line 922

def rewrite_svalue(exp) # :nodoc:
  case exp.last.first
  when :array
    s(:svalue, *exp[1][1..-1])
  when :splat
    exp
  else
    raise "huh: #{exp.inspect}"
  end
end

#splat(sym) ⇒ Object

Return a splatted symbol for sym.



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# File 'lib/ruby2ruby.rb', line 1019

def splat(sym)
  :"*#{sym}"
end

#util_dthing(type, exp) ⇒ Object

Utility method to generate something interpolated.



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# File 'lib/ruby2ruby.rb', line 1026

def util_dthing(type, exp)
  s = []

  # first item in sexp is a string literal
  s << dthing_escape(type, exp.shift)

  until exp.empty?
    pt = exp.shift
    case pt
    when Sexp then
      case pt.first
      when :str then
        s << dthing_escape(type, pt.last)
      when :evstr then
        s << '#{' << process(pt) << '}' # do not use interpolation here
      else
        raise "unknown type: #{pt.inspect}"
      end
    else
      raise "unhandled value in d-thing: #{pt.inspect}"
    end
  end

  s.join
end

#util_module_or_class(exp, is_class = false) ⇒ Object

Utility method to generate ether a module or class.



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# File 'lib/ruby2ruby.rb', line 1055

def util_module_or_class(exp, is_class=false)
  result = []

  name = exp.shift
  name = process name if Sexp === name

  result << name

  if is_class then
    superk = process(exp.shift)
    result << " < #{superk}" if superk
  end

  result << "\n"

  body = []
  begin
    code = process(exp.shift) unless exp.empty?
    body << code.chomp unless code.nil? or code.chomp.empty?
  end until exp.empty?

  unless body.empty? then
    body = indent(body.join("\n\n")) + "\n"
  else
    body = ""
  end
  result << body
  result << "end"

  result.join
end