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how to get the current working directory's absolute path from irb
...ssible from irb? Apparently from a script it's possible using File.expand_path(__FILE__)
6 Answers
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Why return NotImplemented instead of raising NotImplementedError
...
It's because __lt__() and related comparison methods are quite commonly used indirectly in list sorts and such. Sometimes the algorithm will choose to try another way or pick a default winner. Raising an exception would break out of the s...
Event system in Python
...he same, but uses a set instead of a list to store the bag, and implements __call__ which are both reasonable additions.
PyNotify is similar in concept and also provides additional concepts of variables and conditions ('variable changed event'). Homepage is not functional.
axel is basically a bag-o...
What is the difference between __init__ and __call__?
I want to know the difference between __init__ and __call__ methods.
13 Answers
...
unique object identifier in javascript
... var id = 0;
Object.id = function(o) {
if ( typeof o.__uniqueid == "undefined" ) {
Object.defineProperty(o, "__uniqueid", {
value: ++id,
enumerable: false,
// This could go either way, depending on your...
Received fatal alert: handshake_failure through SSLHandshakeException
...ificate validation. In most cases, this will be the cacerts file in the JRE_HOME/lib/security directory. If the location of the trust store has been specified using the JVM system property javax.net.ssl.trustStore, then the store in that path is usually the one used by the client library. If you are...
How to disable GCC warnings for a few lines of code
...
TL;DR: If it works, avoid, or use specifiers like __attribute__, otherwise _Pragma.
This is a short version of my blog article
Suppressing Warnings in GCC and Clang.
Consider the following Makefile
CPPFLAGS:=-std=c11 -W -Wall -pedantic -Werror
.PHONY: all
all: puts
fo...
std::vector performance regression when enabling C++11
...lts are identical:
(I am compiling your original code, with container.push_back(Item());)
$ g++ -std=c++11 -O3 -flto regr.cpp && perf stat -r 10 ./a.out
Performance counter stats for './a.out' (10 runs):
35.426793 task-clock # 0.986 CPUs utilized (...
How to deal with SettingWithCopyWarning in Pandas?
...H5390 and GH5597 for background discussion.]
df[df['A'] > 2]['B'] = new_val # new_val not set in df
The warning offers a suggestion to rewrite as follows:
df.loc[df['A'] > 2, 'B'] = new_val
However, this doesn't fit your usage, which is equivalent to:
df = df[df['A'] > 2]
df['B'] = ...
Is it possible to make abstract classes in Python?
...
# Python 2
from abc import ABCMeta, abstractmethod
class Abstract:
__metaclass__ = ABCMeta
@abstractmethod
def foo(self):
pass
Whichever way you use, you won't be able to instantiate an abstract class that has abstract methods, but will be able to instantiate a subclass th...