i really don't understand python programmers sometimes
October 17, 2025 at 1:31 AM
i really don't understand python programmers sometimes
Noticing a trend of Python programmers using “isinstance” as a guard for type checkers to verify the existence of a method or attribute.
Isinstance is VERY slow for negative cases, esp classes with a few layers of inheritance, or mixins.
Isinstance is VERY slow for negative cases, esp classes with a few layers of inheritance, or mixins.
February 9, 2025 at 1:04 AM
Noticing a trend of Python programmers using “isinstance” as a guard for type checkers to verify the existence of a method or attribute.
Isinstance is VERY slow for negative cases, esp classes with a few layers of inheritance, or mixins.
Isinstance is VERY slow for negative cases, esp classes with a few layers of inheritance, or mixins.
Is a #Python value of a particular type? It's tempting to say:
if type(s) == str:
print('Yes, a string!')
Far better to say:
if isinstance(s, str):
print('Yes, a string!')
Why?
- Works with subclasses
- Second argument can be a tuple of possibilities
if type(s) == str:
print('Yes, a string!')
Far better to say:
if isinstance(s, str):
print('Yes, a string!')
Why?
- Works with subclasses
- Second argument can be a tuple of possibilities
June 6, 2026 at 3:30 PM
Is a #Python value of a particular type? It's tempting to say:
if type(s) == str:
print('Yes, a string!')
Far better to say:
if isinstance(s, str):
print('Yes, a string!')
Why?
- Works with subclasses
- Second argument can be a tuple of possibilities
if type(s) == str:
print('Yes, a string!')
Far better to say:
if isinstance(s, str):
print('Yes, a string!')
Why?
- Works with subclasses
- Second argument can be a tuple of possibilities
What Does `isinstance()` Do in Python? #python
What Does `isinstance()` Do in Python? #python
Learn what isinstance() does in Python and how to use this built-in function to check an object's type. Discover its practical uses along with key limitations.
realpython.com
August 10, 2025 at 3:00 AM
What Does `isinstance()` Do in Python? #python
every time you do an isinstance check, barbara liskov cries
June 7, 2026 at 12:11 AM
every time you do an isinstance check, barbara liskov cries
Dica Python: Verificando tipos com isinstance()
#Python #programadores #bolhatech #linguagemPython #dicapython #isinstance #tipos
#Python #programadores #bolhatech #linguagemPython #dicapython #isinstance #tipos
May 7, 2025 at 9:12 PM
Dica Python: Verificando tipos com isinstance()
#Python #programadores #bolhatech #linguagemPython #dicapython #isinstance #tipos
#Python #programadores #bolhatech #linguagemPython #dicapython #isinstance #tipos
아
RP를 하나하나 체크하지 않으려고 isinstance(record, models.AppBskyFeedPost.Record)일 때에만 라벨링을 하고 있었는데
초무님의 비밀글을 쓰면 app.bsky.richtext.facet#encrypt 렉시콘이 들어가는 부분이 타입 체크에 걸리는 건지 파이썬 atproto SDK에서 JSON을 클래스 객체로 변환하지 못하는 거였음
RP를 하나하나 체크하지 않으려고 isinstance(record, models.AppBskyFeedPost.Record)일 때에만 라벨링을 하고 있었는데
초무님의 비밀글을 쓰면 app.bsky.richtext.facet#encrypt 렉시콘이 들어가는 부분이 타입 체크에 걸리는 건지 파이썬 atproto SDK에서 JSON을 클래스 객체로 변환하지 못하는 거였음
그늘셀프는 왜 항상 동작을 안 하고 있는가...
February 10, 2025 at 7:37 AM
아
RP를 하나하나 체크하지 않으려고 isinstance(record, models.AppBskyFeedPost.Record)일 때에만 라벨링을 하고 있었는데
초무님의 비밀글을 쓰면 app.bsky.richtext.facet#encrypt 렉시콘이 들어가는 부분이 타입 체크에 걸리는 건지 파이썬 atproto SDK에서 JSON을 클래스 객체로 변환하지 못하는 거였음
RP를 하나하나 체크하지 않으려고 isinstance(record, models.AppBskyFeedPost.Record)일 때에만 라벨링을 하고 있었는데
초무님의 비밀글을 쓰면 app.bsky.richtext.facet#encrypt 렉시콘이 들어가는 부분이 타입 체크에 걸리는 건지 파이썬 atproto SDK에서 JSON을 클래스 객체로 변환하지 못하는 거였음
Set one #Python class to inherit from another by putting the parent in ():
class Parent:
pass
class Child(Parent):
pass
Child.__bases__ # who does Child inherit from?
c = Child()
isinstance(c, Child) # True
isinstance(c, Parent) # also True!
class Parent:
pass
class Child(Parent):
pass
Child.__bases__ # who does Child inherit from?
c = Child()
isinstance(c, Child) # True
isinstance(c, Parent) # also True!
May 17, 2026 at 3:38 PM
Set one #Python class to inherit from another by putting the parent in ():
class Parent:
pass
class Child(Parent):
pass
Child.__bases__ # who does Child inherit from?
c = Child()
isinstance(c, Child) # True
isinstance(c, Parent) # also True!
class Parent:
pass
class Child(Parent):
pass
Child.__bases__ # who does Child inherit from?
c = Child()
isinstance(c, Child) # True
isinstance(c, Parent) # also True!
>>> isinstance(False, int)
True
lmao
True
lmao
July 26, 2025 at 9:37 PM
>>> isinstance(False, int)
True
lmao
True
lmao
🐍📰 What Does isinstance() Do in Python? realpython.com/what-does-is...
What Does isinstance() Do in Python? – Real Python
Learn what isinstance() does in Python and how to use this built-in function to check an object's type. Discover its practical uses along with key limitations.
realpython.com
July 21, 2025 at 2:05 PM
🐍📰 What Does isinstance() Do in Python? realpython.com/what-does-is...
# In het taalkundenerdenhoekje
merge = lambda a, b: (a, b)
pf = lambda x: x if isinstance(x, str) else pf(x[0]) + pf(x[1])
print(pf(merge("Hello", merge(", ", merge("world", "!")))))
merge = lambda a, b: (a, b)
pf = lambda x: x if isinstance(x, str) else pf(x[0]) + pf(x[1])
print(pf(merge("Hello", merge(", ", merge("world", "!")))))
May 30, 2026 at 6:43 PM
# In het taalkundenerdenhoekje
merge = lambda a, b: (a, b)
pf = lambda x: x if isinstance(x, str) else pf(x[0]) + pf(x[1])
print(pf(merge("Hello", merge(", ", merge("world", "!")))))
merge = lambda a, b: (a, b)
pf = lambda x: x if isinstance(x, str) else pf(x[0]) + pf(x[1])
print(pf(merge("Hello", merge(", ", merge("world", "!")))))
“That allows for the practice of goose typing, meaning practicing duck typing with the built-in isinstance function.”
Read more 👉 pym.dev/goose-typing/
#Python
Read more 👉 pym.dev/goose-typing/
#Python
Goose typing
In Python you can practice type checking while also practicing duck typing!
pym.dev
September 13, 2026 at 10:47 PM
“That allows for the practice of goose typing, meaning practicing duck typing with the built-in isinstance function.”
Read more 👉 pym.dev/goose-typing/
#Python
Read more 👉 pym.dev/goose-typing/
#Python
Python Tip #242 (of 365):
Prefer isinstance over type for type checking. 🧵
Do this:
isinstance(value, int)
Not this:
type(value) == int
Unlike comparing with type(...), using isinstance respects inheritance.
#Python #DailyPythonTip
Prefer isinstance over type for type checking. 🧵
Do this:
isinstance(value, int)
Not this:
type(value) == int
Unlike comparing with type(...), using isinstance respects inheritance.
#Python #DailyPythonTip
August 30, 2026 at 6:04 PM
Python Tip #242 (of 365):
Prefer isinstance over type for type checking. 🧵
Do this:
isinstance(value, int)
Not this:
type(value) == int
Unlike comparing with type(...), using isinstance respects inheritance.
#Python #DailyPythonTip
Prefer isinstance over type for type checking. 🧵
Do this:
isinstance(value, int)
Not this:
type(value) == int
Unlike comparing with type(...), using isinstance respects inheritance.
#Python #DailyPythonTip
here’s an example of o3 where it hacked a comparison operator to pass a test
October 26, 2025 at 11:51 AM
here’s an example of o3 where it hacked a comparison operator to pass a test
Python Tip #219 (of 365):
Validate your ducks with goose typing 🧵
You can use isinstance() WHILE duck typing. This is sometimes called goose typing (coined by Alex Martelli).
>>> from collections.abc import Iterable
>>> isinstance([1, 2, 3], Iterable)
True
#Python #DailyPythonTip
Validate your ducks with goose typing 🧵
You can use isinstance() WHILE duck typing. This is sometimes called goose typing (coined by Alex Martelli).
>>> from collections.abc import Iterable
>>> isinstance([1, 2, 3], Iterable)
True
#Python #DailyPythonTip
August 8, 2026 at 2:18 AM
Python Tip #219 (of 365):
Validate your ducks with goose typing 🧵
You can use isinstance() WHILE duck typing. This is sometimes called goose typing (coined by Alex Martelli).
>>> from collections.abc import Iterable
>>> isinstance([1, 2, 3], Iterable)
True
#Python #DailyPythonTip
Validate your ducks with goose typing 🧵
You can use isinstance() WHILE duck typing. This is sometimes called goose typing (coined by Alex Martelli).
>>> from collections.abc import Iterable
>>> isinstance([1, 2, 3], Iterable)
True
#Python #DailyPythonTip
python's "there is no character type, only string" decision is ostensibly meant to help beginners out, and python beginners are told "do try:... except:" and to avoid checking types up front
but strings as lists breaks all that, so you have to go "isinstance" to prevent errors
but strings as lists breaks all that, so you have to go "isinstance" to prevent errors
June 15, 2025 at 5:48 PM
python's "there is no character type, only string" decision is ostensibly meant to help beginners out, and python beginners are told "do try:... except:" and to avoid checking types up front
but strings as lists breaks all that, so you have to go "isinstance" to prevent errors
but strings as lists breaks all that, so you have to go "isinstance" to prevent errors
Python、
isinstance(True, int)
がTrueを返しちゃうのか...。
isinstance(True, int)
がTrueを返しちゃうのか...。
December 3, 2025 at 6:03 AM
Python、
isinstance(True, int)
がTrueを返しちゃうのか...。
isinstance(True, int)
がTrueを返しちゃうのか...。
“It's actually possible to use isinstance and practice duck typing at the same time!”
Read more 👉 pym.dev/goose-typing/
#Python
Read more 👉 pym.dev/goose-typing/
#Python
Goose typing
In Python you can practice type checking while also practicing duck typing!
pym.dev
August 13, 2026 at 5:21 PM
“It's actually possible to use isinstance and practice duck typing at the same time!”
Read more 👉 pym.dev/goose-typing/
#Python
Read more 👉 pym.dev/goose-typing/
#Python
Want to build your own code quality tools? 🔍
Python’s `ast` module lets you analyze code like linters do! 💪
Below code snippet extracts all function & method names from a file.
What would you automate? 💡
#Python #AST #CodeQuality
Python’s `ast` module lets you analyze code like linters do! 💪
Below code snippet extracts all function & method names from a file.
What would you automate? 💡
#Python #AST #CodeQuality
![import ast
def get_callables_from_file(filename):
with open(filename, 'r') as f:
content = f.read()
tree = ast.parse(content)
callables = []
def visit_callables(node):
# For top-level functions
if isinstance(node, (ast.FunctionDef, ast.AsyncFunctionDef)):
callables.append(node.name)
# For class methods
elif isinstance(node, ast.ClassDef):
for child in ast.iter_child_nodes(node):
if isinstance(child, (ast.FunctionDef, ast.AsyncFunctionDef)):
callables.append(f"{node.name}.{child.name}")
# Initiate the traversal with the top-level nodes
for top_level_node in tree.body:
visit_callables(top_level_node)
return callables
# Example usage:
filename = 'test_file.py
print(get_callables_from_file(filename))](https://cdn.bsky.app/img/feed_thumbnail/plain/did:plc:uay2bzai5qhnwqcqz7ivsvzg/bafkreic3ux5rv5sjyhloeki464p2qv2a6a7ukvdb327ayjj7vjrcizy7p4)
March 3, 2025 at 10:30 AM
Want to build your own code quality tools? 🔍
Python’s `ast` module lets you analyze code like linters do! 💪
Below code snippet extracts all function & method names from a file.
What would you automate? 💡
#Python #AST #CodeQuality
Python’s `ast` module lets you analyze code like linters do! 💪
Below code snippet extracts all function & method names from a file.
What would you automate? 💡
#Python #AST #CodeQuality
🐍📰 Learn what isinstance() does in Python and how to use this built-in function to check an object's type. Discover its practical uses along with key limitations
#python
#python
What Does isinstance() Do in Python?
Learn what isinstance() does in Python and how to use this built-in function to check an object's type. Discover its practical uses along with key limitations:
realpython.com
October 26, 2025 at 5:30 PM
🐍📰 Learn what isinstance() does in Python and how to use this built-in function to check an object's type. Discover its practical uses along with key limitations
#python
#python
Dica da linguagem Python: Função isinstance()
#Python #programadores #bolhatech #dicas #linguagemPython #dicapython #py
#Python #programadores #bolhatech #dicas #linguagemPython #dicapython #py
October 10, 2024 at 11:22 PM
Dica da linguagem Python: Função isinstance()
#Python #programadores #bolhatech #dicas #linguagemPython #dicapython #py
#Python #programadores #bolhatech #dicas #linguagemPython #dicapython #py
isInstance(variable, numbers.Number)
Or
type(variable) == int or float
Or
type(variable) == int or float
July 18, 2023 at 1:31 PM
isInstance(variable, numbers.Number)
Or
type(variable) == int or float
Or
type(variable) == int or float
🐍 Python Term of the Day: isinstance() (Python’s Built-in Functions)
Returns True if the input object is an instance of a given class, and False otherwise.
Returns True if the input object is an instance of a given class, and False otherwise.
isinstance() | Python’s Built-in Functions – Real Python
Returns True if the input object is an instance of a given class, and False otherwise.
buff.ly
March 22, 2025 at 2:41 PM
🐍 Python Term of the Day: isinstance() (Python’s Built-in Functions)
Returns True if the input object is an instance of a given class, and False otherwise.
Returns True if the input object is an instance of a given class, and False otherwise.
ABC stands for "abstract base class".
Inheriting from an ABC gets you two things:
1. isinstance and issubclass checks will work nicely (i.e. isinstance(x, Sequence))
2. Python will complain LOUDLY if you forgot to implement a required method, instead of failing later in some subtle way
Inheriting from an ABC gets you two things:
1. isinstance and issubclass checks will work nicely (i.e. isinstance(x, Sequence))
2. Python will complain LOUDLY if you forgot to implement a required method, instead of failing later in some subtle way
August 9, 2026 at 12:34 AM
ABC stands for "abstract base class".
Inheriting from an ABC gets you two things:
1. isinstance and issubclass checks will work nicely (i.e. isinstance(x, Sequence))
2. Python will complain LOUDLY if you forgot to implement a required method, instead of failing later in some subtle way
Inheriting from an ABC gets you two things:
1. isinstance and issubclass checks will work nicely (i.e. isinstance(x, Sequence))
2. Python will complain LOUDLY if you forgot to implement a required method, instead of failing later in some subtle way
Today's computation is how to do some kind of thing with a data structure
I am not sure what as I just woke up but the colors look pretty and the code looks like it would do something serious
I am not sure what as I just woke up but the colors look pretty and the code looks like it would do something serious
![def frongle(a, path=(), acc=None):
if acc is None:
acc = []
if isinstance(a, dict):
for c, b in a.items():
frongle(b, path=path + (c,), acc=acc)
elif isinstance(a, list):
for i, b in enumerate(a):
frongle(b, path=path + (i,), acc=acc)
else:
acc.append((path, a)) #type(a).__qualname__
return acc
frongle({ "cid": "bafyreidgyddetlra64yw2oax66fo5k2ziingrowkxzkbc2yn7zgyqlngqu",
"indexed_at": "2026-06-28T12:29:14.902Z",
"is_read": true,
"reason": "like",
"record": {
"created_at": "2026-06-28T12:29:14.902Z",
"subject": {
"cid": "bafyreifvmporo4d7so6mzia2f5aei6k4oyj7fgd6rgja4vl2ldas6nbeme",
"uri": "at://did:plc:ugy6urufh3nb7rd6q6n2w55z/app.bsky.feed.post/3mogec25dbs2v",
"py_type": "com.atproto.repo.strongRef"
},
"via": null,
"py_type": "app.bsky.feed.like"
},
"uri](https://cdn.bsky.app/img/feed_thumbnail/plain/did:plc:5ujaiwdzii5kb6ilzs4tadoz/bafkreihziualefg3ipuqclmxqwnpnv4m3njqy3qmeh7nlcd2qf7a74rkde)
July 2, 2026 at 7:12 AM
Today's computation is how to do some kind of thing with a data structure
I am not sure what as I just woke up but the colors look pretty and the code looks like it would do something serious
I am not sure what as I just woke up but the colors look pretty and the code looks like it would do something serious