fixes #179

fastcore/_nbdev.py

@@ -44,6 +44,10 @@
          "otherwise": "01_basics.ipynb",
          "custom_dir": "01_basics.ipynb",
          "AttrDict": "01_basics.ipynb",
+         "type_hints": "01_basics.ipynb",
+         "annotations": "01_basics.ipynb",
+         "anno_ret": "01_basics.ipynb",
+         "argnames": "01_basics.ipynb",
          "with_cast": "01_basics.ipynb",
          "store_attr": "01_basics.ipynb",
          "attrdict": "01_basics.ipynb",
@@ -165,8 +169,6 @@
          "run_procs": "03_xtras.ipynb",
          "parallel_gen": "03_xtras.ipynb",
          "threaded": "03_xtras.ipynb",
-         "type_hints": "04_dispatch.ipynb",
-         "anno_ret": "04_dispatch.ipynb",
          "lenient_issubclass": "04_dispatch.ipynb",
          "sorted_topologically": "04_dispatch.ipynb",
          "TypeDispatch": "04_dispatch.ipynb",

fastcore/basics.py

@@ -3,17 +3,18 @@
 __all__ = ['defaults', 'ifnone', 'maybe_attr', 'basic_repr', 'is_array', 'listify', 'true', 'NullType', 'null',
            'tonull', 'get_class', 'mk_class', 'wrap_class', 'ignore_exceptions', 'exec_local', 'risinstance', 'Inf',
            'in_', 'lt', 'gt', 'le', 'ge', 'eq', 'ne', 'add', 'sub', 'mul', 'truediv', 'is_', 'is_not', 'in_', 'true',
-           'stop', 'gen', 'chunked', 'otherwise', 'custom_dir', 'AttrDict', 'with_cast', 'store_attr', 'attrdict',
-           'properties', 'camel2snake', 'snake2camel', 'class2attr', 'getattrs', 'hasattrs', 'setattrs', 'try_attrs',
-           'ShowPrint', 'Int', 'Str', 'Float', 'detuplify', 'replicate', 'setify', 'merge', 'range_of', 'groupby',
-           'last_index', 'filter_dict', 'filter_keys', 'filter_values', 'cycle', 'zip_cycle', 'sorted_ex',
-           'negate_func', 'argwhere', 'filter_ex', 'range_of', 'renumerate', 'first', 'nested_attr', 'nested_idx',
-           'num_methods', 'rnum_methods', 'inum_methods', 'fastuple', 'arg0', 'arg1', 'arg2', 'arg3', 'arg4', 'bind',
-           'map_ex', 'compose', 'maps', 'partialler', 'instantiate', 'using_attr', 'Self', 'Self', 'PrettyString',
-           'even_mults', 'num_cpus', 'add_props', 'typed']
+           'stop', 'gen', 'chunked', 'otherwise', 'custom_dir', 'AttrDict', 'type_hints', 'annotations', 'anno_ret',
+           'argnames', 'with_cast', 'store_attr', 'attrdict', 'properties', 'camel2snake', 'snake2camel', 'class2attr',
+           'getattrs', 'hasattrs', 'setattrs', 'try_attrs', 'ShowPrint', 'Int', 'Str', 'Float', 'detuplify',
+           'replicate', 'setify', 'merge', 'range_of', 'groupby', 'last_index', 'filter_dict', 'filter_keys',
+           'filter_values', 'cycle', 'zip_cycle', 'sorted_ex', 'negate_func', 'argwhere', 'filter_ex', 'range_of',
+           'renumerate', 'first', 'nested_attr', 'nested_idx', 'num_methods', 'rnum_methods', 'inum_methods',
+           'fastuple', 'arg0', 'arg1', 'arg2', 'arg3', 'arg4', 'bind', 'map_ex', 'compose', 'maps', 'partialler',
+           'instantiate', 'using_attr', 'Self', 'Self', 'PrettyString', 'even_mults', 'num_cpus', 'add_props', 'typed']
 
 # Cell
 from .imports import *
+import weakref
 
 # Cell
 defaults = SimpleNamespace()
@@ -216,12 +217,37 @@ def __getattr__(self,k): return self[k] if k in self else stop(AttributeError(k)
     def __setattr__(self, k, v): (self.__setitem__,super().__setattr__)[k[0]=='_'](k,v)
     def __dir__(self): return custom_dir(self, list(self.keys()))
 
+# Cell
+def type_hints(f):
+    "Same as `typing.get_type_hints` but returns `{}` if not allowed type"
+    return typing.get_type_hints(f) if isinstance(f, typing._allowed_types) else {}
+
+# Cell
+def annotations(o):
+    "Annotations for `o`, or `type(o)`"
+    res = {}
+    if not o: return res
+    res = type_hints(o)
+    if not res: res = type_hints(getattr(o,'__init__',None))
+    if not res: res = type_hints(type(o))
+    return res
+
+# Cell
+def anno_ret(func):
+    "Get the return annotation of `func`"
+    return annotations(func).get('return', None) if func else None
+
+# Cell
+def argnames(f):
+    "Names of arguments to function `f`"
+    code = f.__code__
+    return code.co_varnames[:code.co_argcount]
+
 # Cell
 def with_cast(f):
     "Decorator which uses any parameter annotations as preprocessing functions"
-    anno = f.__annotations__
-    params = f.__code__.co_varnames[:f.__code__.co_argcount]
-    defaults = dict(zip(reversed(params), reversed(f.__defaults__))) if f.__defaults__ else {}
+    anno,params = annotations(f),argnames(f)
+    defaults = dict(zip(reversed(params), reversed(f.__defaults__ or {})))
     @functools.wraps(f)
     def _inner(*args, **kwargs):
         args = list(args)
@@ -236,10 +262,13 @@ def _inner(*args, **kwargs):
 
 # Cell
 def _store_attr(self, anno, **attrs):
+    stored = self.__stored_args__
     for n,v in attrs.items():
         if n in anno: v = anno[n](v)
         setattr(self, n, v)
-        self.__stored_args__[n] = v
+        try: v = weakref.proxy(v)
+        except TypeError: pass
+        stored[n] = v
 
 # Cell
 def store_attr(names=None, self=None, but='', cast=False, **attrs):
@@ -249,7 +278,7 @@ def store_attr(names=None, self=None, but='', cast=False, **attrs):
     if self: args = ('self', *args)
     else: self = fr.f_locals[args[0]]
     if not hasattr(self, '__stored_args__'): self.__stored_args__ = {}
-    anno = self.__class__.__init__.__annotations__ if cast else {}
+    anno = annotations(self) if cast else {}
     if not attrs:
         ns = re.split(', *', names) if names else args[1:]
         attrs = {n:fr.f_locals[n] for n in ns}
@@ -258,9 +287,9 @@ def store_attr(names=None, self=None, but='', cast=False, **attrs):
     return _store_attr(self, anno, **attrs)
 
 # Cell
-def attrdict(o, *ks):
+def attrdict(o, *ks, default=None):
     "Dict from each `k` in `ks` to `getattr(o,k)`"
-    return {k:getattr(o,k) for k in ks}
+    return {k:getattr(o, k, default) for k in ks}
 
 # Cell
 def properties(cls, *ps):
@@ -668,7 +697,7 @@ def _typeerr(arg, val, typ): return TypeError(f"{arg}=={val} not {typ}")
 def typed(f):
     "Decorator to check param and return types at runtime"
     names = f.__code__.co_varnames
-    anno = f.__annotations__
+    anno = annotations(f)
     ret = anno.pop('return',None)
     def _f(*args,**kwargs):
         kw = {**kwargs}

fastcore/dispatch.py

@@ -1,26 +1,14 @@
 # AUTOGENERATED! DO NOT EDIT! File to edit: nbs/04_dispatch.ipynb (unless otherwise specified).
 
-__all__ = ['type_hints', 'anno_ret', 'lenient_issubclass', 'sorted_topologically', 'TypeDispatch', 'DispatchReg',
-           'typedispatch', 'cast', 'retain_meta', 'default_set_meta', 'retain_type', 'retain_types', 'explode_types']
+__all__ = ['lenient_issubclass', 'sorted_topologically', 'TypeDispatch', 'DispatchReg', 'typedispatch', 'cast',
+           'retain_meta', 'default_set_meta', 'retain_type', 'retain_types', 'explode_types']
 
 # Cell
 from .imports import *
 from .foundation import *
 from .utils import *
-from collections import defaultdict
-
-# Cell
-def type_hints(f):
-    "Same as `typing.get_type_hints` but returns `{}` if not allowed type"
-    return typing.get_type_hints(f) if isinstance(f, typing._allowed_types) else {}
 
-# Cell
-def anno_ret(func):
-    "Get the return annotation of `func`"
-    if not func: return None
-    ann = type_hints(func)
-    if not ann: return None
-    return ann.get('return')
+from collections import defaultdict
 
 # Cell
 def lenient_issubclass(cls, types):
@@ -114,7 +102,7 @@ def returns_none(self, x):
 
     def _attname(self,k): return getattr(k,'__name__',str(k))
     def __repr__(self):
-        r = [f'({self._attname(k)},{self._attname(l)}) -> {getattr(v, "__name__", v.__class__.__name__)}'
+        r = [f'({self._attname(k)},{self._attname(l)}) -> {getattr(v, "__name__", type(v).__name__)}'
              for k in self.funcs.d for l,v in self.funcs[k].d.items()]
         r = r + [o.__repr__() for o in self.bases]
         return '\n'.join(r)

fastcore/imports.py

@@ -1,4 +1,4 @@
-import sys,os,re,shutil,typing,itertools,operator,functools,math,warnings,functools,io
+import sys,os,re,typing,itertools,operator,functools,math,warnings,functools,io
 
 from operator import itemgetter,attrgetter
 from warnings import warn

fastcore/nb_imports.py

@@ -1,6 +1,6 @@
 import numpy as np
 import matplotlib.pyplot as plt
-import numbers,tempfile,pickle,random,inspect
+import numbers,tempfile,pickle,random,inspect,shutil
 
 from PIL import Image
 from numpy import array,ndarray