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Why does += behave unexpectedly on lists?
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The general answer is that += tries to call the __iadd__ special method, and if that isn't available it tries to use __add__ instead. So the issue is with the difference between these special methods.
The __iadd__ special method is for an in-place addition, that i...
How to use a dot “.” to access members of dictionary?
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Install dotmap via pip
pip install dotmap
It does everything you want it to do and subclasses dict, so it operates like a normal dictionary:
from dotmap import DotMap
m = DotMap()
m.hello = 'world'
m.hello
m.hello += '!'
# m...
What is the volatile keyword useful for?
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volatile has semantics for memory visibility. Basically, the value of a volatile field becomes visible to all readers (other threads in particular) after a write operation completes on it. Without volatile, readers could see some non-updated value.
To answer your question: Y...
Principles for Modeling CouchDB Documents
...or instance). Managing the relationships or connections between various, smaller documents can be confusing at first, but CouchDB provides several options for combining disparate pieces into single responses.
The first big one is view collation. When you emit key/value pairs into the results of a m...
Scala: What is a TypeTag and how do I use it?
All I know about TypeTags is that they somehow replaced Manifests. Information on the Internet is scarce and doesn't provide me with a good sense of the subject.
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How assignment works with Python list slice?
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To be clear, "takes a slice of" really means "make a copy of a slice of" which is where part of the confusion comes from.
– Mark Ransom
May 16 '12 at 17:12
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How to do what head, tail, more, less, sed do in Powershell? [closed]
...an above option
gc log.txt | more # or less if you have it installed
gc log.txt | %{ $_ -replace '\d+', '($0)' } # sed
This works well enough for small files, larger ones (more than a few MiB) are probably a bit slow.
The PowerShell Community Extensions include some cmdlets fo...
awk without printing newline
... You might even want to set it "" (no space) to have no separation at all.
– mschilli
Aug 8 '13 at 13:11
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Installing PDO driver on MySQL Linux server
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On Ubuntu you should be able to install the necessary PDO parts from apt using sudo apt-get install php5-mysql
There is no limitation between using PDO and mysql_ simultaneously. You will however need to create two connections to your DB, one with mysql_ and o...
Is it possible to create static classes in PHP (like in C#)?
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You can have static classes in PHP but they don't call the constructor automatically (if you try and call self::__construct() you'll get an error).
Therefore you'd have to create an initialize() function and call it in each method:
<?php
class Hello
{
private static...