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What breaking changes are introduced in C++11?
...nity, whereas C++0x always rounds the result toward 0.
(admittedly not really a compatibility problem for most people).
Valid C++ 2003 code that uses the keyword auto as a storage class specifier may be invalid in C++0x.
Narrowing conversions cause incompatibilities with C++03. For ex...
Date vs DateTime
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Unfortunately, not in the .Net BCL. Dates are usually represented as a DateTime object with the time set to midnight.
As you can guess, this means that you have all the attendant timezone issues around it, even though for a Date object you'd want absolutely no timezone han...
Detecting request type in PHP (GET, POST, PUT or DELETE)
...
By using
$_SERVER['REQUEST_METHOD']
Example
if ($_SERVER['REQUEST_METHOD'] === 'POST') {
// The request is using the POST method
}
For more details please see the documentation for the $_SERVER variable.
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Named routes _path vs _url
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_path helpers provide a site-root-relative path. You should probably use this most of the time.
_url helpers provide an absolute path, including protocol and server name. I've found that I mainly use these in emails when cre...
Dictionary returning a default value if the key does not exist [duplicate]
...Value(key, out value);
and just ignore the return value. However, that really will just return default(TValue), not some custom default value (nor, more usefully, the result of executing a delegate). There's nothing more powerful built into the framework. I would suggest two extension methods:
pu...
No route matches [GET] /assets
...nment. I ran RAILS_ENV=production rake assets:precompile which generated all of my assets in /public/assets. The problem is that when I start my app w/ RAILS_ENV=production rails s thin I get:
...
Any way to properly pretty-print ordered dictionaries?
...well if you don't care about the order of the keys. Personally, I wish the __repr__ for OrderedDict would produce output like this but preserve the order of the keys.
– ws_e_c421
Sep 24 '15 at 15:54
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How can I match a string with a regex in Bash?
...ching in the second example. Inside [[ ]], the * is not expanded as it usually is, to match filenames in the current directory that match a pattern.Your example works, but it's really easy to over-generalize and mistakenly believe that * means to match anything in any context. It only works like t...
C# Lazy Loaded Automatic Properties
... 4.0 Lazy<T> type to create this pattern
private Lazy<string> _someVariable =new Lazy<string>(SomeClass.IOnlyWantToCallYouOnce);
public string SomeVariable => _someVariable.Value;
This code will lazily calculate the value of _someVariable the first time the Value expression i...
Which is faster in Python: x**.5 or math.sqrt(x)?
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I've now run it 3 times on codepad.org and all three times a() was much faster than b().
– Jeremy Ruten
Nov 29 '08 at 1:38
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