def __init__(self, is_intaractive_run, an_errhandler):
""" EvalVisitorを初期化して応答する．
"""
self.is_test = False
self.is_intaractive_run = is_intaractive_run
self.errhandler = an_errhandler
self.scopes = ScopeList()
self.is_break = False
self.is_return = False
self.return_value = UnitXObject(value=None, varname=None, unit=None, token=None, is_none=True)
this_dir, _ = os.path.split(__file__)
data_path = os.path.join(this_dir, Constants.SYSTEM_UNIT_DATA)
self.unit_manager = UnitManager(data_path) # Sets a database(data/unit_table.dat) for calculating units.
self.stdlib = Stdlib()
self.NULL_UNITX_OBJ = UnitXObject(value=None, varname=None, is_none=True, unit=Unit(), token=None)
#
# Sets a mediator to each classes for a management,
# because this class is a mediator class.
# Also, UnitXObject, Unit, Scope classes have to create many new instances.
# So, We set a mediator by using classmethod.
#
self.scopes.set_mediator(self)
self.unit_manager.set_mediator(self)
self.stdlib.set_mediator(self)
UnitXObject.set_mediator(self)
Unit.set_mediator(self)
Scope.set_mediator(self)
DefinedFunction.set_mediator(self)
UnitXObject.manager = self.get_unit_manager()
UnitXObject.scopes = self.get_scopes()
