def defer_demo():
def lazy(frame, obj):
obj.load()
return obj
class Lazily:
def load(self):
self.value = 10
x = Lazily()
setrwatch({id(x): lazy})
print(x.value)
def promise(frame, obj):
return obj.value
class Promise:
@property
def value(self):
return 10
x = Promise()
setrwatch({id(x): promise})
print(x)
def defer_demo():
def lazy(frame, obj):
obj.load()
return obj
class Lazily:
def load(self):
self.value = 10
x = Lazily()
setrwatch({id(x): lazy})
print(x.value)
def promise(frame, obj):
return obj.value
class Promise:
@property
def value(self):
return 10
x = Promise()
setrwatch({id(x): promise})
print(x)
def debug_demo(x='some data'):
from inspect import getframeinfo
def view(frame, obj):
info = getframeinfo(frame)
msg = 'Access to {!r} (@{}) at {}:{}:{}'
print(msg.format(obj, hex(id(obj)), info.filename, info.lineno, info.function))
return obj
setrwatch({id(x): view})
print(getrwatch())
def f(x):
x # ← here
f(x) # ← here
def f(x):
def g():
x # ← here
return g
f(x)() # ← here
class Foo:
def __init__(self, x):
self.x = x # ← here
def __call__(self):
return self.x # ← here
@property
def value(self):
return self.x # ← here
foo = Foo(x) # ← here
foo()
foo.value
x = 10 # not here (rebind, no push)
def sandbox_demo(x='some data'):
def forbid(frame, obj):
raise SystemError("can't touch this")
setrwatch({id(x): forbid})
try:
# x
pass
except:
pass
def sandbox_demo(x='some data'):
def forbid(frame, obj):
raise SystemError("can't touch this")
setrwatch({id(x): forbid})
try:
# x
pass
except:
pass
def indirection_demo():
def pointer(frame, obj):
return obj()
def make_pointer(x):
cell = [x]
pointer = lambda: cell[0]
def repoint(x):
cell[0] = x
return pointer, repoint
y, z = 1234, 4567
x, x_ = make_pointer(y)
setrwatch({id(x): pointer})
print(x)
x_(z)
print(x)
def debug_demo(x='some data'):
from inspect import getframeinfo
def view(frame, obj):
info = getframeinfo(frame)
msg = 'Access to {!r} (@{}) at {}:{}:{}'
print(
msg.format(obj, hex(id(obj)), info.filename, info.lineno,
info.function))
return obj
setrwatch({id(x): view})
print(getrwatch())
def f(x):
x # ← here
f(x) # ← here
def f(x):
def g():
x # ← here
return g
f(x)() # ← here
class Foo:
def __init__(self, x):
self.x = x # ← here
def __call__(self):
return self.x # ← here
@property
def value(self):
return self.x # ← here
foo = Foo(x) # ← here
foo()
foo.value
x = 10 # not here (rebind, no push)
def indirection_demo():
def pointer(frame, obj):
return obj()
def make_pointer(x):
cell = [x]
pointer = lambda: cell[0]
def repoint(x):
cell[0] = x
return pointer, repoint
y, z = 1234, 4567
x, x_ = make_pointer(y)
setrwatch({id(x): pointer})
print(x)
x_(z)
print(x)
def mutable_demo(x='some data', y='other data'):
def view(frame, obj):
print('Saw access to {!r}'.format(obj))
return obj
watches = {id(x): view}
setrwatch(watches)
x
watches[id(y)] = view
y
class Predicate(dict):
def dispatch(self, frame, obj):
for pred, func in self.items():
if pred(obj):
func(frame, obj)
def __getitem__(self, _):
return self.dispatch
from collections.abc import Sized
watches = Predicate({lambda o: isinstance(o, Sized) and len(o) > 9: view})
setrwatch(watches)
x, y
def mutable_demo(x='some data', y='other data'):
def view(frame, obj):
print('Saw access to {!r}'.format(obj))
return obj
watches = {id(x): view}
setrwatch(watches)
x
watches[id(y)] = view
y
class Predicate(dict):
def dispatch(self, frame, obj):
for pred, func in self.items():
if pred(obj):
func(frame, obj)
def __getitem__(self, _):
return self.dispatch
from collections.abc import Sized
watches = Predicate({lambda o: isinstance(o, Sized) and len(o) > 9: view})
setrwatch(watches)
x, y
def f():
x = object()
setrwatch({id(x): view})
print({hex(k): v for k, v in (getrwatch() or {}).items()})
print('x =', x)
def f():
x = object()
setrwatch({id(x): view})
print({hex(k): v for k,v in (getrwatch() or {}).items()})
print('x =', x)
def __exit__(self, exc_type, exc_val, exc_tb):
setrwatch({})
def __enter__(self):
setrwatch(defaultdict(lambda: self.rwatch))
def __enter__(self):
setrwatch(defaultdict(lambda: add_white_noise_to_complex))
def __enter__(self):
setrwatch(defaultdict(lambda: debug_view_for_any_object))
# In[5]:
get_ipython().run_cell_magic('bash', '', 'tmpdir=$(mktemp -d)\ncd $tmpdir\ngit clone https://github.com/dutc/rwatch\ncd rwatch/src/\nmake\nls -larth ./rwatch.so\nfile ./rwatch.so\n# cp ./rwatch.so /where/ver/you/need/ # ~/publis/notebook/ for me')
# Anyhow, if `rwatch` is installed, we can import it, and it enables two new functions in the `sys` module:
# In[6]:
import rwatch
from sys import setrwatch, getrwatch
setrwatch({}) # clean any previously installed rwatch
getrwatch()
# Finally, we need the [`collections`](https://docs.python.org/3/library/collections.html) module and its [`defaultdict`](https://docs.python.org/3/library/collections.html#collections.defaultdict) magical datastructure.
# In[7]:
from collections import defaultdict
# ----
# ## Defining a debugging context manager, just to try
#
# This is the first example given in [James presentation]() at PyCon Canada 2016.
# In[5]:
get_ipython().run_cell_magic('bash', '', 'tmpdir=$(mktemp -d)\ncd $tmpdir\ngit clone https://github.com/dutc/rwatch\ncd rwatch/src/\nmake\nls -larth ./rwatch.so\nfile ./rwatch.so\n# cp ./rwatch.so /where/ver/you/need/ # ~/publis/notebook/ for me')
# Anyhow, if `rwatch` is installed, we can import it, and it enables two new functions in the `sys` module:
# In[6]:
import rwatch
from sys import setrwatch, getrwatch
setrwatch({}) # clean any previously installed rwatch
getrwatch()
# Finally, we need the [`collections`](https://docs.python.org/3/library/collections.html) module and its [`defaultdict`](https://docs.python.org/3/library/collections.html#collections.defaultdict) magical datastructure.
# In[7]:
from collections import defaultdict
# ----
# ## Defining a debugging context manager, just to try
#
# This is the first example given in [James presentation]() at PyCon Canada 2016.
def __enter__(self):
setrwatch(defaultdict(lambda: debug_view_for_any_object))
def __enter__(self):
setrwatch(defaultdict(lambda: add_white_noise_to_complex))
def __exit__(self, exc_type, exc_val, exc_tb):
setrwatch({})
def __enter__(self):
setrwatch(defaultdict(lambda: self.rwatch))