Class: Pione::Lang::PackageBindingDeclaration

Inherits:
Declaration
  • Object
show all
Defined in:
lib/pione/lang/declaration.rb

Overview

PackageBindingDeclaration is a declaration for package binding sentences.

Instance Method Summary collapse

Methods inherited from Declaration

#eval!, inherited

Methods included from Util::Positionable

#line_and_column, #pos, #set_source_position

Instance Method Details

#eval(env) ⇒ Object

Update variable table and package table.



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# File 'lib/pione/lang/declaration.rb', line 78

def eval(env)
  # variable name
  var = get_reference(env, expr1, Variable)

  # check the parent package
  parent_package = expr2.eval(env)

  # evaluate expr2 and get new package instance
  child_pieces = parent_package.pieces.map do |parent_piece|
    # definition of parent package
    parent_definition = env.package_get(parent_piece)
    # generate new id
    child_id = Util::PackageID.generate(env, parent_piece.name)
    # validate parameter set
    parent_piece.param.pieces.each do |param_piece|
      param_piece.table.keys do |key|
        unless parent_definition.param_definition.has_key?(key.name)
          raise ParamError.new(key.name, parent_piece.package_id)
        end
      end
    end
    # update package table
    definition = PackageDefinition.new(
      package_id: child_id,
      parent_ids: [parent_piece.package_id],
      param_definition: parent_definition.param_definition,
      param: parent_definition.param.merge(parent_piece.param)
    )
    # create child piece
    child_piece = parent_piece.set(package_id: child_id, parent_ids: [parent_piece.package_id])
    # register the child to package table
    env.package_set(child_piece, definition)
    # result
    child_piece
  end
  child_package = PackageExprSequence.of(*child_pieces)

  # update variable table with the result
  VariableBindingDeclaration.new(var, child_package).eval(env)
end