r"""
Load and save Sage objects with standardized names
==================================================
The ``saveable`` module defines the ``Savable`` class:
a mixin class with methods that load and save Sage objects with standardized names.
AUTHORS:
- Paul Leopardi (2016-08-04): initial version
- Paul Leopardi (2017-04-01): saveable.py based on persistent.py
"""
from builtins import object
import os
import os.path
from sage.misc.persist import load, save
class Saveable(object):
r"""
A mixin class with methods that load and save objects with standardized names.
EXAMPLES:
::
sage: from boolean_cayley_graphs.saveable import Saveable
sage: class ListSaveable(list, Saveable):
....: def __init__(self, value):
....: list.__init__(self, value)
....:
sage: a = ListSaveable([1])
sage: a[0]
1
"""
@classmethod
def mangled_name(cls, name, dir=None):
r"""
Convert a name for an object into a standardized name.
INPUT:
- ``cls`` -- The current class.
- ``name`` -- The name for the object.
- ``dir`` -- (Optional, default=None)
The directory name to be used for the file name of the object.
The default value of None means the current directory.
OUTPUT:
A string containing the directory path and the standardized name.
EXAMPLES:
::
sage: from boolean_cayley_graphs.saveable import Saveable
sage: class ListSaveable(list, Saveable):
....: def __init__(self, value):
....: list.__init__(self, value)
....:
sage: ListSaveable.mangled_name('a')
'ListSaveable__a'
sage: ListSaveable.mangled_name('a', dir='b')
'b/ListSaveable__a'
"""
standardized_name = cls.__name__ + "__" + name
if dir == None:
return standardized_name
else:
return os.path.join(dir, standardized_name)
@classmethod
def load_mangled(cls, name, dir=None):
r"""
Load an object based on its standardized name.
INPUT:
- ``cls`` -- the class object.
- ``name`` -- string: the file name suffix (without ".obj")
part of the standardized name.
- ``dir`` -- string, optional. The directory where the object
was saved. Default is None, meaning the current directory.
OUTPUT:
The object that was saved in the file referred to by the
standardized name and the directory.
EXAMPLES:
::
sage: import os
sage: from boolean_cayley_graphs.boolean_function_improved import BooleanFunctionImproved as BFI
sage: a = BFI([0,1,0,0])
sage: d = tmp_dir()
sage: a.save_mangled("a", dir=d)
sage: b = BFI.load_mangled("a", dir=d)
sage: a == b
True
sage: BFI.remove_mangled("a", dir=d)
sage: os.rmdir(d)
"""
return cls(load(cls.mangled_name(name, dir=dir)))
@classmethod
def remove_mangled(cls, name, dir=None):
r"""
Remove a saved object based on its standardized name.
INPUT:
- ``cls`` -- the class object.
- ``name`` -- string: the file name suffix (without ".obj")
part of the standardized name.
- ``dir`` -- string, optional. The directory where the object
was saved. Default is None, meaning the current directory.
OUTPUT:
None.
EFFECT:
The file containing the saved object is deleted.
EXAMPLES:
::
sage: from boolean_cayley_graphs.boolean_function_improved import BooleanFunctionImproved as BFI
sage: a = BFI([0,1,0,0])
sage: d = tmp_dir()
sage: a.save_mangled("a", dir=d)
sage: file_name = BFI.mangled_name("a.sobj", dir=d)
sage: os.path.isfile(file_name)
True
sage: BFI.remove_mangled("a", dir=d)
sage: os.path.isfile(file_name)
False
sage: os.rmdir(d)
"""
file_name = cls.mangled_name(name + ".sobj", dir=dir)
if os.path.isfile(file_name):
os.remove(file_name)
def save_mangled(self, name, dir=None):
r"""
Save an object using its standardized name.
INPUT:
- ``self`` -- the current object.
- ``name`` -- string: the file name suffix (without ".obj")
part of the standardized name.
- ``dir`` -- string, optional. The directory where the object
is to be saved. Default is None, meaning the current directory.
OUTPUT:
None.
EFFECT:
A file is created and the object ``self`` is saved into the file.
EXAMPLES:
::
sage: from boolean_cayley_graphs.boolean_function_improved import BooleanFunctionImproved as BFI
sage: a = BFI([0,1,0,0])
sage: d = tmp_dir()
sage: a.save_mangled("a", dir=d)
sage: file_name = BFI.mangled_name("a.sobj", dir=d)
sage: os.path.isfile(file_name)
True
sage: BFI.remove_mangled("a", dir=d)
sage: os.rmdir(d)
"""
save(self, self.__class__.mangled_name(
name,
dir=dir))
