__all__ = ('Array',)
import typing
import collections.abc
from .core import (
_WithStorageSlotAndTD,
TypeDesc,
Slot,
CopyAction,
actions_apply_copy,
SpecialTypeDesc,
actions_append,
)
from ..types import SizedArray
[docs]
class Array[T, S: int](
_WithStorageSlotAndTD, collections.abc.Sequence, SizedArray[T, S]
):
"""
Constantly sized array that can be persisted on the blockchain
"""
_item_desc: TypeDesc
_len: int
__slots__ = ('_item_desc', '_len', '_off', '_storage_slot')
[docs]
def __init__(self):
"""
This class can't be created with ``Array()``
:raises TypeError: always
"""
raise TypeError('this class can not be instantiated by user')
[docs]
def __len__(self) -> int:
return self._len
@staticmethod
def _view_at(item_desc: TypeDesc, le: int, slot: Slot, off: int) -> 'Array':
slf = Array.__new__(Array)
slf._item_desc = item_desc
slf._len = le
slf._storage_slot = slot
slf._off = off
return slf
def _map_index(self, idx: int) -> int:
le = len(self)
if idx < 0:
idx += le
if idx < 0 or idx >= le:
raise IndexError(f'index out of range {idx} not in 0..<{le}')
return idx
@typing.overload
def __getitem__(self, idx: typing.SupportsIndex) -> T: ...
@typing.overload
def __getitem__(self, idx: slice) -> 'Array': ...
[docs]
def __getitem__(self, idx: typing.SupportsIndex | slice) -> T | 'Array':
"""
Get element by index or a view over a sub-range by slice.
:param idx: integer index or slice (step must be 1)
:returns: single element for int index, ``Array`` view for slice
:raises IndexError: when integer index is out of range
:raises KeyError: when slice step is not 1
"""
if not isinstance(idx, slice):
idx = self._map_index(idx.__index__())
return self._item_desc.get(
self._storage_slot, self._off + idx * self._item_desc.size
)
else:
start, stop, step = idx.indices(len(self))
if step != 1:
raise KeyError('negative step is not supported')
le = max(stop - start, 0)
return Array._view_at(
self._item_desc,
le,
self._storage_slot,
self._off + start * self._item_desc.size,
)
[docs]
def __setitem__(self, idx: int, val: T) -> None:
"""
Set element at the given index.
:param idx: integer index (supports negative indexing)
:param val: value to set
:raises IndexError: when index is out of range
"""
idx = self._map_index(idx)
self._item_desc.set(self._storage_slot, self._off + idx * self._item_desc.size, val)
[docs]
def __iter__(self):
for i in range(len(self)):
yield self[i]
class _ArrayDesc(SpecialTypeDesc):
_len: int
__slots__ = ('item_desc', 'view_ctor', '_len')
def __init__(self, item_desc: TypeDesc, le: int):
self._len = le
def new_array():
ret = Array.__new__(Array)
ret._len = le
return ret
SpecialTypeDesc.__init__(self, item_desc, new_array)
cop: list[CopyAction] = []
for _i in range(le):
actions_append(cop, item_desc.copy_actions)
TypeDesc.__init__(self, le * item_desc.size, cop)
def set(self, slot: Slot, off: int, val: Array | list) -> None:
assert len(val) == self._len
if isinstance(val, list):
for i in range(self._len):
self.item_desc.set(slot, off + i * self.item_desc.size, val[i])
else:
actions_apply_copy(self.copy_actions, slot, off, val._storage_slot, val._off)
