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Iterate over object attributes in python
...t;>> dir(obj)
['__class__', '__delattr__', '__dict__', '__doc__', '__format__', '__getattribute__', '__hash__', '__init__', '__module__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '__weakref__', 'bar', 'foo', 'func']
You...
Append an object to a list in R in amortized constant time, O(1)?
...th it, so by all means also see some of the comments below. One suggestion for list types:
newlist <- list(oldlist, list(someobj))
In general, R types can make it hard to have one and just one idiom for all types and uses.
...
How do exceptions work (behind the scenes) in c++
...the standard library, based on these tables (_ZTI11MyException is typeinfo for MyException).
OK, that was not actually a surprise for me, I already knew how this compiler did it. Continuing with the assembly output:
.text
.align 2
.p2align 4,,15
.globl _Z20my_throwing_functionb
.ty...
What's the common practice for enums in Python? [duplicate]
What's the common practice for enums in Python? I.e. how are they replicated in Python?
4 Answers
...
Code Golf: Lasers
...uple ways to shave off 6 more characters:
s!.!$t{$s++}=$&!ge,$s=$r+=99for<>;%d='>.^1<2v3'=~/./g;($r)=grep$d|=$d{$t{$_}},%t;
{$_=$t{$r+=(1,-99,-1,99)[$d^=3*/\\/+m</>]};/[\/\\ ]/&&redo}die/x/?true:false,$/
The first line loads the input into %t, a table of the board wh...
How to save all the variables in the current python session?
...one option is to use the 'pickle' module. However, I don't want to do this for 2 reasons:
7 Answers
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Importing from builtin library when module with same name exists
...ple of the more appropriate way to load a module directly from a file path for python >= 3.5:
import importlib.util
import sys
# For illustrative purposes.
import tokenize
file_path = tokenize.__file__ # returns "/path/to/tokenize.py"
module_name = tokenize.__name__ # returns "tokenize"
spec...
How to “perfectly” override a dict?
...shuts the ABC up.
from collections.abc import MutableMapping
class TransformedDict(MutableMapping):
"""A dictionary that applies an arbitrary key-altering
function before accessing the keys"""
def __init__(self, *args, **kwargs):
self.store = dict()
self.update(dic...
Using OR in SQLAlchemy
...you have a long list of things to OR, you can do filter(or_(User.name == v for v in ('Alice', 'Bob', 'Carl')))
– robru
Aug 26 '15 at 20:21
69
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Relative imports in Python 2.7
...ule. A file is loaded as the top-level script if you execute it directly, for instance by typing python myfile.py on the command line. It is loaded as a module if you do python -m myfile, or if it is loaded when an import statement is encountered inside some other file. There can only be one top-...