TypeProf::Type

 
               # File typeprof-0.21.2/lib/typeprof/type.rb, line 23
def self.match?(ty1, ty2)
  # both ty1 and ty2 should be global
  # ty1 is always concrete; it should not have type variables
  # ty2 might be abstract; it may have type variables
  case ty2
  when Type::Var
    { ty2 => ty1 }
  when Type::Any
    {}
  when Type::Union
    subst = nil
    ty2.each_child_global do |ty2|
      # this is very conservative to create subst:
      # Type.match?( int | str, int | X) creates { X => int | str } but should be { X => str }???
      subst2 = Type.match?(ty1, ty2)
      next unless subst2
      subst = Type.merge_substitution(subst, subst2)
    end
    subst
  else
    case ty1
    when Type::Var then raise "should not occur"
    when Type::Any
      subst = {}
      ty2.each_free_type_variable do |tyvar|
        subst[tyvar] = Type.any
      end
      subst
    when Type::Union
      subst = nil
      ty1.each_child_global do |ty1|
        subst2 = Type.match?(ty1, ty2)
        next unless subst2
        subst = Type.merge_substitution(subst, subst2)
      end
      subst
    else
      if ty2.is_a?(Type::ContainerType)
        # ty2 may have type variables
        return nil if ty1.class != ty2.class
        ty1.match?(ty2)
      elsif ty1.is_a?(Type::ContainerType)
        nil
      else
        ty1.consistent?(ty2) ? {} : nil
      end
    end
  end
end
            

 
               # File typeprof-0.21.2/lib/typeprof/type.rb, line 73
def self.merge_substitution(subst1, subst2)
  if subst1
    subst1 = subst1.dup
    subst2.each do |tyvar, ty|
      if subst1[tyvar]
        subst1[tyvar] = subst1[tyvar].union(ty)
      else
        subst1[tyvar] = ty
      end
    end
    subst1
  else
    subst2
  end
end
            

 
               # File typeprof-0.21.2/lib/typeprof/type.rb, line 5
def initialize
  raise "cannot instantiate abstract type"
end
            

 
               # File typeprof-0.21.2/lib/typeprof/type.rb, line 89
def each_child
  yield self
end
            

 
               # File typeprof-0.21.2/lib/typeprof/type.rb, line 93
def each_child_global
  yield self
end
            

 
               # File typeprof-0.21.2/lib/typeprof/type.rb, line 97
def each_free_type_variable
end
            

 
               # File typeprof-0.21.2/lib/typeprof/type.rb, line 11
def globalize(_env, _visited, _depth)
  self
end
            

 
               # File typeprof-0.21.2/lib/typeprof/type.rb, line 19
def limit_size(limit)
  self
end
            

 
               # File typeprof-0.21.2/lib/typeprof/type.rb, line 15
def localize(env, _alloc_site, _depth)
  return env, self
end
            

 
               # File typeprof-0.21.2/lib/typeprof/type.rb, line 100
def union(other)
  return self if self == other # fastpath

  ty1, ty2 = self, other

  case
  when ty1.is_a?(Union)
    ty1_types = ty1.types
    ty1_elems = ty1.elems
  when ty1.is_a?(Array) || ty1.is_a?(Hash)
    ty1_types = Utils::Set[]
    ty1_elems = {[ty1.class, ty1.base_type] => ty1.elems}
  else
    ty1_types = ty1_elems = nil
  end

  case
  when ty2.is_a?(Union)
    ty2_types = ty2.types
    ty2_elems = ty2.elems
  when ty2.is_a?(Array) || ty2.is_a?(Hash)
    ty2_types = Utils::Set[]
    ty2_elems = {[ty2.class, ty2.base_type] => ty2.elems}
  else
    ty2_types = ty2_elems = nil
  end

  if ty1_types && ty2_types
    ty = ty1_types.sum(ty2_types)
    all_elems = ty1_elems.dup || {}
    ty2_elems&.each do |key, elems|
      all_elems[key] = union_elems(all_elems[key], elems)
    end
    all_elems = nil if all_elems.empty?

    Type::Union.create(ty, all_elems)
  elsif ty1_types
    Type::Union.create(ty1_types.add(ty2), ty1_elems)
  elsif ty2_types
    Type::Union.create(ty2_types.add(ty1), ty2_elems)
  else
    Type::Union.create(Utils::Set[ty1, ty2], nil)
  end
end