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What is the strict aliasing rule?
... way, maybe get some warnings, have it compile fine, only to have weird unexpected behavior when you run the code.
(GCC appears somewhat inconsistent in its ability to give aliasing warnings, sometimes giving us a friendly warning and sometimes not.)
To see why this behavior is undefined, we have to...
Assign pandas dataframe column dtypes
...
Since 0.17, you have to use the explicit conversions:
pd.to_datetime, pd.to_timedelta and pd.to_numeric
(As mentioned below, no more "magic", convert_objects has been deprecated in 0.17)
df = pd.DataFrame({'x': {0: 'a', 1: 'b'}, 'y': {0: '1', 1: '2'}, 'z...
ng-app vs. data-ng-app, what is the difference?
... difference is simple - there is absolutely no difference between the two except that certain HTML5 validators will throw an error on a property like ng-app, but they don't throw an error for anything prefixed with data-, like data-ng-app.
So to answer your question, use data-ng-app if you would li...
Multi-line commands in GHCi
..., you can rely on type inference to work out a signature for you. In your example, the following is sufficient:
Prelude> let addTwo x y = x + y
If you really want a definition with a type signature, or your definition spans over multiple lines, you can do this in ghci:
Prelude> :{
Prelude|...
What is the use of the JavaScript 'bind' method?
...this inside the function to be the parameter passed to bind().
Here's an example that shows how to use bind to pass a member method around that has the correct this:
var myButton = {
content: 'OK',
click() {
console.log(this.content + ' clicked');
}
};
myButton.click();
var looseClick ...
Copy a variable's value into another
...
b = a;
The code actually does nothing at all, because a and b are the exact same thing. The code is the same as if you'd written:
b = b;
which obviously won't do anything.
Why does your new code work?
b = { key1: a.key1, key2: a.key2 };
Here you are creating a brand new object with the {....
How do I remove all non-ASCII characters with regex and Notepad++?
...
This expression will search for non-ASCII values:
[^\x00-\x7F]+
Tick off 'Search Mode = Regular expression', and click Find Next.
Source: Regex any ASCII character
...
Base64 encoding and decoding in client-side Javascript
...
Some browsers such as Firefox, Chrome, Safari, Opera and IE10+ can handle Base64 natively. Take a look at this Stackoverflow question. It's using btoa() and atob() functions.
For server-side JavaScript (Node), you can use Buffers to decode.
If you are...
is_null($x) vs $x === null in PHP [duplicate]
...e related isset() language construct checks whether the variable actually exists before doing the null check. So isset($undefinedVar) will not throw a notice.
Also note that isset() may sometimes return true even though the value is null - this is the case when it is used on an overloaded object, i...
What is the purpose of Rank2Types?
...can write a function that takes different types of arguments without this extension, you can't write a function that uses its argument as different types in the same invocation.
For example the following function can't be typed without this extension because g is used with different argument types ...