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When should I use nil and NULL in Objective-C?
... technically, they are exactly equal, you can send messages to both nil and to NULL. Idiomatically though nil is usually used to represent an object
– cobbal
Oct 14 '09 at 5:43
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C++ Const Usage Explanation
...hanged, to an int that cannot be changed: the only difference between this and const int& is that it can be null
const int* const& means a reference to a constant pointer to a constant int. Usually pointers are not passed by reference; const int* & makes more sense because it would mean...
rmagick gem install “Can't find Magick-config”
...stall the rmagick gem. I am on Snowleopard 10.6 using RVM, Ruby 1.9.2-head and Rails 3.05. Responses to similar questions recommended installing ImageMagick, which I successfully did. Other suggested installing the "libmagick9-dev library", however, I can not figure out how to do this.
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Object reference not set to an instance of an object.Why doesn't .NET show which object is `null`?
Regarding this .NET unhandled exception message:
5 Answers
5
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How do I parse a string to a float or int?
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You should handle ValueError if you want to be safe
– Joe Bobson
Sep 9 '18 at 13:20
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“Origin null is not allowed by Access-Control-Allow-Origin” error for request made by application ru
I'm developing a page that pulls images from Flickr and Panoramio via jQuery's AJAX support.
17 Answers
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Warning on “diff.renamelimit variable” when doing git push
I'm pushing the local commit to the remote git server and got the following warning messages:
2 Answers
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What is the difference between self-types and trait subclasses?
...njection in Scala, including the Cake Pattern. If you Google "Cake Pattern and Scala", you'll get many links, including presentations and videos. For now, here is a link to another question.
Now, as to what is the difference between a self type and extending a trait, that is simple. If you say B ex...
Catching an exception while using a Python 'with' statement
To my shame, I can't figure out how to handle exception for python 'with' statement. If I have a code:
4 Answers
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How to send an email with Gmail as provider using Python?
...rver.ehlo()
server.starttls()
Also you should really create From:, To: and Subject: message headers, separated from the message body by a blank line and use CRLF as EOL markers.
E.g.
msg = "\r\n".join([
"From: user_me@gmail.com",
"To: user_you@gmail.com",
"Subject: Just a message",
"",...