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Why is parenthesis in print voluntary in Python 2.7?
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In Python 2.x print is actually a special statement and not a function*.
This is also why it can't be used like: lambda x: print x
Note that (expr) does not create a Tuple (it results in expr), but , does. This likely results in the confusion between...
C++ Erase vector element by value rather than by position? [duplicate]
... @jak: Take a look at the description of remove(): It moves all values not equal to the value passed to the beginning of the range [begin,end). With your example in the question you'd get 5,9,2,0,7,7. As remove() however returns an iterator to the new end, vec.erase() can remove the o...
Why is there no logical xor in JavaScript?
...r. Mainly because it's not useful. Bitwise XOR is extremely useful, but in all my years of programming I have never needed a logical XOR.
If you have two boolean variables you can mimic XOR with:
if (a != b)
With two arbitrary variables you could use ! to coerce them to boolean values and then u...
django - why is the request.POST object immutable?
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It's a bit of a mystery, isn't it? Several superficially plausible theories turn out to be wrong on investigation:
So that the POST object doesn't have to implement mutation methods? No: the POST object belongs to the django.http.QueryDict class, which implements a full set ...
change type of input field with jQuery
... or part of their security model, but jQuery isn't specific):
// We can't allow the type property to be changed (since it causes problems in IE)
if ( name == "type" && jQuery.nodeName( elem, "input" ) && elem.parentNode )
throw "type property can't be changed";
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What's the difference between Perl's backticks, system, and exec?
...It never returns true, because if the command is found it never returns at all.
There is also no point in returning STDOUT, STDERR or exit status of the command.
You can find documentation about it in perlfunc,
because it is a function.
system
executes a command and your Perl script is con...
hadoop No FileSystem for scheme: file
...tem, hadoop-hdfs for DistributedFileSystem) each contain a different file called org.apache.hadoop.fs.FileSystem in their META-INFO/services directory. This file lists the canonical classnames of the filesystem implementations they want to declare (This is called a Service Provider Interface impleme...
PHP - Get key name of array value
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array_filter() can be used if you need to return all matching results instead of just the first matching one, as it preserves keys.
– Mike Lyons
Nov 27 '14 at 1:40
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Android - Activity vs FragmentActivity? [duplicate]
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ianhanniballake is right. You can get all the functionality of Activity from FragmentActivity. In fact, FragmentActivity has more functionality.
Using FragmentActivity you can easily build tab and swap format. For each tab you can use...
Using sections in Editor/Display templates
I want to keep all of my JavaScript code in one section; just before the closing body tag in my master layout page and just wondering the best to go about it, MVC style.
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