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Why are Where and Select outperforming just Select?
...);
int result2 = myCollection.Sum(mc => mc.IsValid ? mc.Value : 0);
Now here's the kicker:
LINQ uses deferred execution. Thus, while it may appear that result1 iterates over the collection twice, it actually only iterates over it once. The Where() condition is actually applied during the S...
How do I parse JSON with Objective-C?
...f the OS X v10.7 and iOS 5 launches, probably the first thing to recommend now is NSJSONSerialization, Apple's supplied JSON parser. Use third-party options only as a fallback if you find that class unavailable at runtime.
So, for example:
NSData *returnedData = ...JSON data, probably from a web r...
How do I remove all non-ASCII characters with regex and Notepad++?
I searched a lot, but nowhere is it written how to remove non-ASCII characters from Notepad++.
7 Answers
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Importing variables from another file?
...iables from file1 without flooding file2's namespace, use:
import file1
#now use file1.x1, file2.x2, ... to access those variables
To import all variables from file1 to file2's namespace( not recommended):
from file1 import *
#now use x1, x2..
From the docs:
While it is valid to use from ...
PermGen elimination in JDK 8
... get a java.lang.OutOfMemoryError: PermGen error.
The JDK 8 HotSpot JVM is now using native memory for the representation of class metadata and is called Metaspace. Read More>>
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Anonymous recursive PHP functions
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Mind Blown! Thanks a lot! How did I not know about this till now? The amount of application I have for recursive anonymous functions is huge. Now I can finally loop through nested structures in layouts without having to explicitly define a method and keep all my lay...
How can Perl's print add a newline by default?
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The real danger comes from the fact that all code will now add newlines, even code in other people's modules that weren't expecting it. Imagine networking code that would have sent the message "helo\r\n" that now sends "helo\r\n\n".
– Chas. Owens
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How do I get the current absolute URL in Ruby on Rails?
...otocol}#{request.host_with_port}#{request.fullpath}", since request.url is now deprecated.
For Rails 2:
You can write request.url instead of request.request_uri. This combines the protocol (usually http://) with the host, and request_uri to give you the full address.
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Are the days of passing const std::string & as a parameter over?
...rgely gone. He suggested that writing a function such as the following is now preferable:
13 Answers
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How do I get the object if it exists, or None if it does not exist?
...u can do it this way:
go = Content.objects.filter(name="baby").first()
Now go variable could be either the object you want or None
Ref: https://docs.djangoproject.com/en/1.8/ref/models/querysets/#django.db.models.query.QuerySet.first
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