I am studying the functools library in python. However, when I copy the examples from the documentation for the decorator
@singledispatch
I do not get the same results as the ones that are reported on the docs.
from functools import singledispatch
@singledispatch
def fun(arg, verbose=False):
if verbose:
print("Let me just say,", end=" ")
print(arg)
@fun.register
def _(arg: int, verbose=False):
if verbose:
print("Strength in numbers, eh?", end=" ")
print(arg)
@fun.register
def _(arg: list, verbose=False):
if verbose:
print("Enumerate this:")
for i, elem in enumerate(arg):
print(i, elem)
Should evaluate to:
>>> fun("Hello, world.")
Hello, world.
>>> fun("test.", verbose=True)
Let me just say, test.
>>> fun(42, verbose=True)
Strength in numbers, eh? 42
>>> fun(['spam', 'spam', 'eggs', 'spam'], verbose=True)
Enumerate this:
0 spam
1 spam
2 eggs
3 spam
But in my juypter notebook it just doesn't.
>>> fun("Hello, world.")
Hello, world.
>>> fun("test.", verbose=True)
Let me just say, test.
>>> fun(42, verbose=True)
Let me just say, 42
>>> fun(['spam', 'spam', 'eggs', 'spam'], verbose=True)
Let me just say, ['spam', 'spam', 'eggs', 'spam']
