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What is the most pythonic way to check if an object is a number?
...: 0 + x
except TypeError: canadd=False
else: canadd=True
The presence of __add__ per se tells you nothing useful, since e.g all sequences have it for the purpose of concatenation with other sequences. This check is equivalent to the definition "a number is something such that a sequence of such t...
TypeError: got multiple values for argument
...ng of the box to another function, relaying all extra arguments.
def color_box(color, *args, **kwargs):
painter.select_color(color)
painter.draw_box(*args, **kwargs)
Then the call
color_box("blellow", color="green", height=20, width=30)
will fail because two values are assigned to colo...
warning about too many open figures
...) will remove a specific figure instance from the pylab state machine (plt._pylab_helpers.Gcf) and allow it to be garbage collected.
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Iterate over object attributes in python
... object attributes are callable, such as methods.
>>> dir(obj)
['__class__', '__delattr__', '__dict__', '__doc__', '__format__', '__getattribute__', '__hash__', '__init__', '__module__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subcla...
Using OR in SQLAlchemy
...
From the tutorial:
from sqlalchemy import or_
filter(or_(User.name == 'ed', User.name == 'wendy'))
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Placeholder in UITextView
...uble.
UIPlaceHolderTextView.h:
#import <Foundation/Foundation.h>
IB_DESIGNABLE
@interface UIPlaceHolderTextView : UITextView
@property (nonatomic, retain) IBInspectable NSString *placeholder;
@property (nonatomic, retain) IBInspectable UIColor *placeholderColor;
-(void)textChanged:(NSNotif...
What is a good pattern for using a Global Mutex in C#?
...e : IDisposable
{
//edit by user "jitbit" - renamed private fields to "_"
public bool _hasHandle = false;
Mutex _mutex;
private void InitMutex()
{
string appGuid = ((GuidAttribute)Assembly.GetExecutingAssembly().GetCustomAttributes(typeof(GuidAttribute), false).GetValue(...
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...
Cannot kill Python script with Ctrl-C
...
Looks like in python3 you can pass daemon=True to Thread.__init__
– Ryan Haining
Aug 14 '18 at 0:57
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Should a return statement be inside or outside a lock?
...als init (
[0] int32 CS$1$0000,
[1] object CS$2$0001)
L_0000: ldsfld object Program::sync
L_0005: dup
L_0006: stloc.1
L_0007: call void [mscorlib]System.Threading.Monitor::Enter(object)
L_000c: call int32 Program::GetValue()
L_0011: stloc.0
L_0012: leav...