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Why do I get AttributeError: 'NoneType' object has no attribute 'something'?
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You have a variable that is equal to None and you're attempting to access an attribute of it called 'something'.
foo = None
foo.something = 1
or
foo = None
print(foo.something)
Both will yield an AttributeError: 'NoneType'
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Difference between fmt.Println() and println() in Go
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println is an built-in function (into the runtime) which may eventually be removed, while the fmt package is in the standard library, which will persist. See the spec on that topic.
For language developers it is handy to have a println without dependencies, but the way to go is to use the f...
How to unset a JavaScript variable?
I have a global variable in JavaScript (actually a window property, but I don't think it matters) which was already populated by a previous script but I don't want another script that will run later to see its value or that it was even defined.
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Does the C++ standard mandate poor performance for iostreams, or am I just dealing with a poor imple
...f the work can
be avoided. With a slightly smarter
linker than is typically used, it is
possible to remove some of these
inefficiencies. This is discussed in
§6.2.3 and §6.2.5.
Since the report was written in 2006 one would hope that many of the recommendations would have been incorpor...
Is it possible to rotate a drawable in the xml description?
...ate in XML:
<?xml version="1.0" encoding="utf-8"?>
<rotate xmlns:android="http://schemas.android.com/apk/res/android"
android:fromDegrees="90"
android:toDegrees="90"
android:pivotX="50%"
android:pivotY="50%"
android:drawable="@drawable/mainmenu_back...
AngularJS - convert dates in controller
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All solutions here doesn't really bind the model to the input because you will have to change back the dateAsString to be saved as date in your object (in the controller after the form will be submitted).
If you don't need t...
How to remove all the occurrences of a char in c++ string
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Basically, replace replaces a character with another and '' is not a character. What you're looking for is erase.
See this question which answers the same problem. In your case:
#include <algorithm>
str.erase(std::remove(s...
How to bind a List to a ComboBox?
...ry = (Country)comboBox1.SelectedItem;.
If you want the ComboBox to dynamically update you'll need to make sure that the data structure that you have set as the DataSource implements IBindingList; one such structure is BindingList<T>.
Tip: make sure that you are binding the DisplayMember to...
Execute a terminal command from a Cocoa app
...;
NSFileHandle *file = pipe.fileHandleForReading;
NSTask *task = [[NSTask alloc] init];
task.launchPath = @"/usr/bin/grep";
task.arguments = @[@"foo", @"bar.txt"];
task.standardOutput = pipe;
[task launch];
NSData *data = [file readDataToEndOfFile];
[file closeFile];
NSString *grepOutput = [[NSS...
how to check redis instance version?
... command showed the new version, but the server needed to be restarted manually to launch the new version, whereas INFO correctly reported the old version.
– X-Cubed
Apr 13 '17 at 3:08
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