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Why is “import *” bad?
...espace (might shadow some other object from previous import and you won't know about it).
Because you don't know exactly what is imported and can't easily find from which module a certain thing was imported (readability).
Because you can't use cool tools like pyflakes to statically detect errors i...
What is the purpose of the word 'self'?
...stance attributes. That's why assigning to an instance attribute needs to know what instance to assign to, and that's why it needs self..
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Converting Long to Date in Java returns 1970
...nt of whole seconds since the same epoch reference of 1970-01-01T00:00Z.
Know Your Data
People use various precisions in tracking time as a number since an epoch. So when you obtain some numbers to be interpreted as a count since an epoch, you must determine:
What epoch?Many epochs dates have been...
Overriding superclass property with different type in Swift
...ore than one superclass declaration
I've only checked Xcode 6.0 GM as of now.
Unfortunately, you'll have to wait until Apple fixes this.
I've submitted a bug report too. 18518795
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append to url and refresh page
...aram=42';
We don't have to alter the entire url, just the query string, known as the search attribute of location.
When you are assigning a value to the search attribute, the question mark is automatically inserted by the browser and the page is reloaded.
...
What are the “standard unambiguous date” formats for string-to-date conversion in R?
...here a better solution than needing to specify the format?
Yes, there is now (ie in late 2016), thanks to anytime::anydate from the anytime package.
See the following for some examples from above:
R> anydate(c("01 Jan 2000", "01/01/2000", "2015/10/10"))
[1] "2000-01-01" "2000-01-01" "2015-10...
Why is it string.join(list) instead of list.join(string)?
...ace UCS2/4. To calculate total buffer length of UTF-8 strings it needs to know character coding rule.
At that time, Python had already decided on a common sequence interface rule where a user could create a sequence-like (iterable) class. But Python didn't support extending built-in types until 2.2....
Displaying the build date
...s well and good except it means nothing to most of the users, who want to know if they have the latest build - they tend to refer to it as "last Thursday's" rather than build 1.0.8.4321.
...
Turn a simple socket into an SSL socket
...);
}
void ShutdownSSL()
{
SSL_shutdown(cSSL);
SSL_free(cSSL);
}
Now for the bulk of the functionality. You may want to add a while loop on connections.
int sockfd, newsockfd;
SSL_CTX *sslctx;
SSL *cSSL;
InitializeSSL();
sockfd = socket(AF_INET, SOCK_STREAM, 0);
if (sockfd< 0)
{
/...
Can dplyr package be used for conditional mutating?
...
dplyr now has a function case_when that offers a vectorised if. The syntax is a little strange compared to mosaic:::derivedFactor as you cannot access variables in the standard dplyr way, and need to declare the mode of NA, but it ...